I'm guessing that you've already told your mother that you're straight.

Beyond that, I don't think there are any magic words you can use to convince her when she has it set in her mind that she's right. Or else she's just passive-aggressively trying to get you into a relationship already.

It sounds as though you just might have to deal with her speculation until you "prove" to her that you're straight by having a boyfriend. However, don't let this pressure you into relationships that you don't want.

Maybe it's not such a horrible thing that she thinks you're a lesbian. I'm not suggesting you lie to her or not tell her you're straight, but if she really believes that you're gay, it might soften her homophobia.

How about telling her something like this...

"Hey Mom, I know you're just trying to look out for me and make sure I'm happy in college, and I really appreciate your concern. I think you're a little off base in assuming that my lack of boyfriend means I'm a lesbian, or even that not having a boyfriend is necessarily a problem. Weren't you (or your straight friends) ever single for a while in college?

Yeah, there are a lot of guys at my school... but just because there are a lot of them doesn't mean I'm willing to date just any one! I don't want to just be in a relationship, I want to be in a relationship with a guy who is good for me, and I haven't found that person yet. Plus, it's still early in the year! If I had just met someone a few weeks ago and already had a committed boyfriend, wouldn't you be a little concerned that I was moving really fast without getting to know a guy? And on top of all that, school work is challenging and I'm busy making friends.

"When or if I find a guy who I really connect with, I'll be sure to let you know. But until then, please don't bother me about who I'm dating. I know you're just trying to look out for me, but I think the best person to decide whom to date and when is me."

I'd focus on the fact that you didn't go to college to get dates, but to learn. If she wants to turn that into homophobia that's her own prejudice. I'd consistently turn the conversation away from the debate over your sexuality- I don't see anything fruitful coming out of that, but I do see the potential to reinforce her ideas about lesbians and compromise your own feminist beliefs. It's hard to teach by example that you see nothing wrong with lesbianism when you're spending so much time contesting the idea that you might be one. Back away from that controversy, explain that you've already told her as much as you're going to on the topic, and that she's free to disbelieve you if she feels like it (because you can't control that anyway). Then talk about how involved you are in classes and other aspects of college, about how you're investing money and time into getting your degree (and not an Mrs.), and explain that it's hurtful when she puts so much emphasis on dating.

It sounds like she's pretty old-fashioned, if she's thinking that the purpose (or even a purpose) of going to college is to get a man. So I suggest that you fight old-fashioned fire with old-fashioned fire - my grandparents used to have a saying about girls going to technical schools/science institutions that "the odds are good, but the goods are odd." (Meaning the guys that went there were the 1950's equivalent of computer geeks.) While personally I think it's a little mean to refer to guys at science institutions as "goods," and as "odd" goods at that, you have to deliver the message that you think she'll understand. So next time she makes a crack about you being lesbian, just bust out with "the odds are good, but the goods are odd." She'll get the picture.

Just say they are a bunch of nerds that would rather spend time with their calculators than with a women.

Then laugh with her about 'boys and their toys'.

And bam! Mother/daughter bonding time can commence.

This happened to my girlfriend, shortly before we met. Her primary focus had been on getting her master's degree and working simultaneously, leaving her not much time for a relationship. We met shortly after she attained her M.A. and was finally able to have the time to date.

I think what surprised me most about the DC area was hearing woman after woman tell me how difficult it was to find a decent guy and how part of it was due to the fact that there were far more women than men. In your situation, where the reverse is true, I would just inform her that your studies and your career are more important right now. (Don't let me put words in your mouth).

Clearly your mother is just going to think what she wants to. Tell her you're not in school to get your MRS degree and school/academics is your focus right now.

I'd, personally, make some joke about going to Lilith Fair or an Ani Concert* or something because it's my sense of humor, but I would crack some sort of joke or light hearted comment.

*Seen her 4 times and LOVE HER, btw.

You should prolly go have lots and lots of sex, get preggers, have a shotgun wedding, and drop out.
Of course I'm being sarcastic.
I actually had this problem (sort of) when I was in high school. I went to an Arts school where all the guys were kinda geeky, gay, or schlubs. And that wasn't my type (at the time -- now I'm dating an uber video gamer lol!!! Just to show you that you can't judge a book by it's cover!!!), so I didn't really date AT ALL. I was introverted and didn't get out much either, so that prolly helped. MY mom and several aunts kept asking me if I was gay, but eventually they stopped. I repeatedly told them I wasn't. Since you've already told your mother the same, I think the only thing to do is keep saying it.

Tell your mom you have different priorities right now and that focusing on a career is more important. If she has been through a divorce or a close relative or friend has been, bring up the fact it's more important to have that career so if something does happen (divorce, death, he runs out on you) you will have a way to support yourself. I'm not sure how many times I heard from my mom about someone she worked with or through a friend that someone wound up divorced or the spouse ran out (heck, there was a case where the wife ran out and the husband was left with the kids and everything) and the spouse that remained was left with the expenses. You never know what is going to happen and it's great to always be prepared for yourself.

I would communicate to her that you have rather high standards in the men you date. Don't let her convince you that you need to lower the standards. There are guys out there who will meet the requirements. Let her know that as little contact as you have had with these guys in your classes, they aren't your type. I'm not sure if I would give her a little ray of hope if you were to say "Who knows, in a couple of months i might like one of them". I'd be worried your mother would get too excited by how you describe her.

I don't get asked this often, but when I do, I like to launch into a spiel on, "are you kidding me?! I don't have TIME to date!" Describe in detail how time-consuming your schoolwork, volunteering, part-time jobs, research, etc., are, and make it as boring to her as possible. (For example, include the minute details of specific math/science exercises and rambly, meandering stories about some irritating obstacle you encountered recently.) Do this every time she asks. I definitely don't get asked this often. :)

This doesn't clear up the problem of convincing her of your heterosexuality or commitment to your degree, but that sounds like a problem far over my head. I gave up on actively seeking my mother's approval a long time ago. She's a Protestant SAHM who never really had a career and started having kids pretty early. I'm an agnostic-atheist getting a 4yr degree in a male-dominated field so I can have an intellectually-stimulating career and provide a cushy life for my future cat-babies (no people-babies for me thanks). So yeah, we get along by just not talking about certain things.

Hey...so my mom is exactly the same way- to the point that she has actually stopped asking me the questions she used to ask me once a month: "Are you sure you're not gay?" and "Do you have a boyfriend yet?" Honestly, you will NEVER convince your mom with words that you're straight, so I'd ignore it. I don't really know where she comes from on the religious spectrum, but my mom expects me to have a boyfriend ASAP and get married ASAP so I can have children. She will NEVER understand that I have different priorities- and while it's unfortunate, it is likely that while you are at this part of your life, your mother will never understand your choices. I know I sound defeated (mainly because I am.)....but it is reality.

Just keep telling her: 'The odds are good, but the goods are odd.'

With parents, while we may love them, we don't neccesarily like them, huh?

A proper response would be: "What's wrong with being a lesbian? Would you love me any less if I were?" and leave it at that. If she answers "yes," then I think it's time to find a new mother.

While I don't get the "you're gay" card, I get the "when are you going to get married so I can have grandchildren to play with?" card a lot.

This time when I was visiting, I jokingly told her that I got someone pregnant. She freaked out, because, of course, babies are only worthy if they're not born out of wedlock.

Do you have a father, or another relative who does understand and can talk to your mother for you? Maybe with another member of family telling your mum that she's misunderstanding you and stressing you out as a result, you might get less antagonism.

Its not that I am not attracted to the guys here, I just don't want to date them.

she is a religious wing nut, and while I am a christian I don't buy into the whole women must submit to men thing at all

When all else fails, I'd push her buttons. (But that's me. I gave up seeking my mother's approval long ago.)

I'd tell her you don't feel the need to date right now because the hook-up opportunities are endless.

(BTW you can change your Display Name to match your User Name under "Edit Profile.")

My mom was the same way. She thought that just because I didn't date much, I must be lesbian. I don't think she changed her mind really until I got married (to a man).

If she starts in on you, I'd firmly explain to her that, "Mom, I'm not a lesbian. I'm a student, and a busy one, and when I meet the right guy, you'll be the first to know." And if she continues to harp on you, just say, "Mom, stop. We already had this conversation, remember? Now, what about..." and change the subject.

I'm sorry but I chuckled a bit at this. It really hit home for me.

I'm an engineering student, femme and conventionally attractive. I am one of 7 girls in the entire department. People constantly ask silly questions like "oh ho ho, I bet you have to fend boys off left and right!" Yeah, right. That is exactly how it works. Honestly, most of us(generally speaking, YMMV) are very othered. Either that or treated 100% like one of the guys either because that's what comes natural or they don't know how to treat us so they just default to what they know.

I just default to quoting PhD comics. "The odds are good, but the goods are odd."

http://www.phdcomics.com/comics/archive.php?comicid=8

I also like to emphasize that political/social beliefs are really, really important to me and that I am a minority there in that regard. I haven't met very many feminist men at my department.