My friend Chanel is a tomboy but isn't sure she likes girls because she isn't sure of herself what should I tell her or what should I do to make her come out her shell?

I have been so grateful for this site, it has been wonderful in making me more comfortable about my relationship. Basically, it comes down to the fact that my boyfriend and I are at the point where sex would seem like the next natural step, but every time we get close, we end up having a discussion instead. We have been together for a year now, are 21 and are both virgins, and while he is completely ready, I am not sure I am. We have engaged in all other sexual activities, manual, oral, etc, but I cannot seem to wrap my head around the idea of having actual intercourse.I have told him why - nervous, scared that the relationship will change, that it will become all about the physical, etc. And while he says he wants me to be comfortable, I think that he is really getting frustrated. I feel like even though we are not having sex yet, everything is now about that. And the last time we were together, it was all about him...physically I mean. And he is never like that. I just don't know if I am making too big a deal out of the whole sex thing. I mean we have talked the issue to death already, and I want to know what sex with him would be like....is there anything I can do to take the pressure off of myself and to therefore, take the pressure off our relationship?