My friend always ask me to go get drunk with him. I wouldnt mind doing it but I wont because my girlfriend would get mad at me and I just want to avoid the fight. I wouldnt have a problem with it but she drinks with her friends all the time, and in some situations I ask her not to because there just not good situations. Is it normal for her to have these hypocritical rules? Should I do something about it?

Why would she know what is good for you and not the other way around. Heck, maybe she doesn't want you to drink because she cheats on you when she does and she thinks you may do the same.
All's these women know about what's going on between you and your girlfriend is that she is exacting control on you and they love it.
I don't care what her reasons are for not letting you drink. It's BULLSHIT that she can drink and you can't, and know what ice found? Usually when people are insecure like that it's because theyre doing something wrong. Ex) lots of people, if they're cheating, will accuse you of chesting to cover up for themselves.
Also, this post is making me hate my gender. Why did so many other girls agree with your gf? Cus i think she sounds kinda psycho
If not, she doesn't have a say.
I personally choose not to drink because despite loving my husband being drunk turns me into a horny slut. My husband on the other hand never gets like that so occasionaly he will have a drink...
I just think it's all about how people act and how responcible people are. Some men get aggresive when drunk.
If none of this is the case then maybe your girlfriend is just being controlling. Maybe sit down and try and talk to her about it.
She KNOWS what she's capable of (ex. Not cheating, stopping at too many, ignoring dumb friends), if you're away from her, how will she know if you can do the same?
She may be worried about you doing something (drunk or not) with your friends around (ex. My bf is COMPLETELY different with his friends, that terrifies me, because I don't know if his values carry over to that side of him).
Talk to her. You may have to set a drink limit, being her along sometimes, keep frequent contact with her on nights out.. Whether or not you're concerned for her, you can ask her to match your limitations as well, so as to be more fair.
Maybe she's loyal enough to trust herself because she knows she won't do anything, she just doesn't fully trust you? Maybe shes worried that you'll cheat (she knows she won't ever cheat on you) . It's not really a bad thing... And you shouldn't listen to everyone.. Unless you really know what's best for you. Try having a controlled ego. :)