Ok this is really bothering me and I need some advice. I met this guy in January. We have been "friends"...if you know what I mean, since then. We go through periods where we see each other a lot and periods where we don't see each other for a month straight. Well I hadn't seen him for about a month and a half because I found out he was seeing someone else. Well a week ago he calls me and wants me to come over to his house with him and some of his brothers. At first I said no, I couldn't go back to the way we were before. But he called again and I gave in. I went over there and he was all about me. It was great. But I should know that is just the way he is when he wants what he wants. Well he called me two days later when I was at home. Then on Monday he had a party and me and some of my friends went. We ended up going upstairs. Well all the sudden out of the blue he asks me to be his girlfriend. I was like WTF??

As much as I want this to happen in my heart, I know it will be a bad thing. For one, he is 19 and I am 23. I am graduating in a year and he doesn't even go to class. He drinks every night of the week. And he has lied to me a lot about stupid things, so I don't know when to really take him seriously. I know it would not work, but I can't bring my self to say no. I don't really understand why I care about him but I do. Deep down I think this is what I have wanted the whole time. But I just don't trust him.
My friends have all told me what they think and they all agree to stay away from him. I understand where they are coming from I just don't know if I can do that. Has anyone else had this problem? What do you think I should do?
Sorry this was so long.