Am I wrong to feel this way?

My girlfriend wants to party. I don't. I don't like drinking or partying and I think it's dumb if someone HAS to have alcohol or party to have fun. Here's the thing. I just turned 25 and she's 19... (this may be the difference here as I'm more mature and she's still growing up). I personally don't want her going out to parties getting drunk and stuff. I kno people are going to be like, man you need to trust her and blah blah blah. This isn't a trust issue, as I know she loves me and wouldn't do anything to put that into jeopardy. I just don't want her to go out partying when she could be spending the time with me either bowling or going to the movies or a dinner date. She says she does it to meet friends and parties are dumb unless you're drinking. I ask her why can't she meet people in a more respectable environment?? Like at the gym or in cl or in her dorm... I don't and possibly never will, get why people have to have alcohol for a good time... Sorry it's so long, but please answer why I felt so hurt when she KNOWINGLY went to a party and drank when I asked her not to? It's like she didn't care at all about my feelings. We've been dating 8 months. Lived together this summer.