Mom airing her opinions on my sexuality

I came out to my parents more than a year ago, my mom found me with a girl... no nothing dirty and she said "I want to understand, do you like girls, it's not weird It's normal these days." To me that day she seemed cool about it and for a while after and it was a relief since I had been dreading having that conversation with her. Anyways I guess she thought it would blow over and that it was just a phase (it's not)

After I did, my brother came out as gay and my mom told me about it, and I said oh that's nice, I'm not the only one and she responded saying "your not a lesbian though are you". Recently it's been even worst though, asking me if something happened with a girl that made me change my mind or if a guy did something to me I didn't like, or saying you can't have children though, and telling me not to post anything about homosexuality on facebook and that she still hopes I'll end up with a man.

Anyways, it doesn't bug me that she's not 100% about it, what bothers me is that she has to air her opinions about it, I would be okay knowing she didn't accept it if she didn't have to talk to me about It all the time, I mean I would prefer if she did accept it of course, anyways the big thing that bothers me is that she doesn't say anything to my brother about it.

In his mind she accepts it, she doesn't bring it up to him or anything, she even makes conversation with his boyfriend and I do not understand why she can't do the same for me. She's also told me that she wished me and him were switched, that I was the boy and vice versa.

Every time she brings it up it puts my whole mood down, it almost makes me feel bad about myself for being the way I am, but it is the way I am. What do I do, I don't want to always have to hear about how I should be dating guys and blah blah blah should I just tell her not to talk to me about it. She doesn't even like me telling other people that I am gay, I think its embarrassing for her... it seriously bugs the crap out of me. :c