I swear she's changing for the worse, and idk what to do!?

I swear my girlfriend is changing like for the worse.... How do you let her kow? Like whats the next step? For example, she used to be a big time partier and drank and used to kiss any guy that came to her. She changed a year before I met her and went good again. That's good because I'm the one who never even drank before! So it was hard for me to forget about her past. So we've been going out for about a year now and things have been pretty good up tell recently. I swear she never wants to have anymore (let me tell you we used to almost every freaking chance we got the first couple months of our relationship). Now I swear I have to pretty much beg for it... I also got this job that makes me work at six in the morning every morning and that has made me awnry all the time. So add those two things together and you get fight after fight after fight! So now we went to a party last week and there was drinking and hooka, to me all that is just gross but fun to hang out with every one. So we went for the party and dancing, later after telling her how much I didn't wanna be there anymore she tells me she wants to try hooka and kinda drink! So now that opens up a whole lot of crap because I thought she was completely done with it all but to hear that just broke my heart. Every time I try to open up to her she gets mad... She doesn't realize how much this is hurting me to hear her wanting to do it all again. Then today she tells me her friend wants to get us fake ids JUST to go to a dance club witch I think is bull soooo much drinking and I just don't want to be at that situation. It hurt me soooo bad again to hear that she now wants to do this? I'm just tearing up thinking about how much she's changing... Idk what to do because If I open up to her she'll just find a way to get mad at me about it by saying "oh It's just so we can get in to dance" what she doesn't get is I don't want to be around this and I don't want her around it either. I can't talk to her either! Help?