This starts with a friend of mine, let's call him C. After I met C I kind of fell in love with him, but I got over it (more or less) and we've been good friends ever since.
I now have a boyfriend, and... Well, it's recently occurred to me just how similar he is to C. Personality, appearance, the lot. There are a few things about my boyfriend that irritate me, but they're all qualities that C doesn't have.
No it's not. It's not fair to you or him that you're using him as a substitute. If you really like C, let him know, although i cna completely understand why you're hesitant to do so b/c i'm in the same situation right now, having a crush on a friend.
yeah, i suppose you're right.
I don't think telling C will help anything, though... I already know there's no way he would be interested, so all it'd serve to do is probably ruin our friendship.
It's obviously not good to go out with Mr. B. Continuing that will only hurt both of you more. I'm sure that you don't want to hurt and neither does he so it's best to just break it off for both of your sakes.
As far as the tell him/don't tell him problem it's mostly up to you. Only you know how you feel. Though, I will suggest that you tell him that way you have no regrets and the thought of him and you together isn't darkening your every thought. There is also a chance that, if he doesn't like you that way, you can still be friends.