I think that you need to stop putting such restrictions on yourself. My boyfriend at 18 years old wanted a wife, not a girlfriend. He is so much more relaxed now and I feel less confined in my role, I am just me, not his potential wife etc.
Personally, I don't think there is anything wrong with alcohol, but I am an Aussie, and we like our grog. But, at the same time, now I am a bit older, I only drink once every three months or so anyway.
Hardcore music and no drugs I know happens a lot (most of my friends don't do drugs at all) and we are into punk music and other harder stuff. I don't think music should be a criteria though because I have found all sorts of different music through my boyfriend's friends that I just love. I would never have even heard of some of it if it weren't for them.
You might need to have your definite no go zones, for me that is smoking. I could never go out with a smoker. I think though, give a person a chance and don't think about five years later, just two days later or something. If it doesn't work out, you might be upset for a while, but you'll eventually find someone who perhaps when you least expected it, was the best friend you ever met.
It sounds like you might be meeting girls in the wrong places too. I met my guy on a train going to a rock concert about 2000km away. We have ages to chat because there was nowhere we could go.
Didn't you say you were only 20? You have plenty of time, don't feel like you have been left on the shelf.