I'm stressing out and going insane. What should I do about my relationship?

Okay, so I've been in a relationship with a girl for over 9 months now, and at first it felt like the best thing ever, now it's stressing me out. It's something about her that just really, really turn me off at times. She makes me dislike stuff that I was once interested in. Like, I've always had a good relationship with god, and I always felt like he has a plan for is all. But the way she slang god around, using him against everything that she doesn't agree with morally, annoys me. I was stressed out before we hooked up but not so much. She's blaming my zodiac sign for the way I act towards her, not knowing it's her that's making me act that way. I'm an Aquarius, and she claims my personality fits the role of an Aquarius, as far as being stressed out and detached in our relationship. And she said if I was born as another sign, I may not act the way that I act. What pisses me off, is the fact that I told her what I went through in high school and over the years, which has an affect on how I may be with some people. Plus, she's overly sensitive. Sometimes, not a lot, I joke around with sarcasm, and it'll piss her off, making her call me sinister. Her mother takes up most of her time, and it leaves me high and dry because we can only talk when she's free. And usually it's not a balanced enough time for me because at the time that I'm busy, she's free or busy, and at the time that I'm free, she doesn't have much time for me. I'm so pissed thinking about it, that I can't even get across what I really want to say. And all of this stress is making me gain weight, when I'm usually an active person but I've been to stressed to workout.