Hides was having a saga with a friend of hers (a male), who had confessed some "feelings" for her (unrequited, of course. Because that's how these sagas work), and we got to talking about friendship and sex. people like this guy usually think that if you're friends with someone and you have this crush, eventually things will happen and you'll get together. I know because I've been there. But it's not just about taking the friendship and adding sex, even though that what these people (and once, me) think will happen. The friendship doesn't work anymore, because you effectively end that in favor of this new thing, which ends up being not what you envisioned. I don't know if it's because sex ruins everything, or the emotions tied up in that do, or if the closeness causes people to go nutters. Or the nudity. But whatever it is, the friendship can't take it and is almost always ruined in the end. This was covered on what is one of the best episodes of Seinfeld ever, where Jerry and Elaine decide to "take this, and add that," and sleep together. It didn't even work for them, because there is always "The Other."
The point: I would rather keep my friends and get my sex elsewhere (or not, as the case may be). No matter how strongly I may feel about them, you just can't trade friendship for sex. Obviously, sometimes the planets align and it works out for the best, but for my money, my friendships are more valuable to me than that. I'll just have to find somebody who isn't my friend and sleep with them. Then I have nothing to lose.