DaveKerwin said:
Oscar, what country do you live in? Are both of you under age?
It sounds like you have not had the guts to tell her directly how it makes you feel, you said "I think she kinda knows it bugs me". Kinda knows is not good enough, get real with her, show her more of your heart on this. If she does not care, that tells you a lot about her. I don't think it would be absurd for you to request that she only has a maximum of one beverage when out with her friends, or perhaps that she only drinks while with you (assuming this is all legal).
I think Dave has a great point here... you said in your post that you only
think she knows how you feel about it. I think its time that, if you are serious about this girl, you have a serious conversation about how her being in those situations makes you feel. Perhaps she has no idea, and if you told her, she would understand.
One thing I would strongly advice you against, is putting her on a guilt trip. I know its the cliche bible verse, but really try and think of 1 Cor 13:
Love is not rude, it is not self-seeking, it is not easily angered, it keeps no record of wrongs. Love does not delight in evil but rejoices with the truth.
Just sit her down, and tell her exactly how it makes you feel. LIke I said in my previous post, and like Dave said, if she dosen't respond well you may want to re consider who you spend your time with.
I also have to ask myself... is she a christian? Are you? Going out to the clubs (even when or if you are not drinking) is still kinda sketchy... there is so much temptation at clubs, from drinking and everything else. Even going there with the intentions of NOT drinking, dosen't mean that your not gonna drink. Trust me, I went through it. Eventually I ended up drinking again and I was back down a road I was down once before. I quickly got out of it, but it can happen.
Anyways I hope everything works out, but I strongly suggest that you sit down and have a chat with her.