Honestly, make sure you show your boyfriend your lemmy posts lusting after him if you haven't; he'll be on top of the world and feel very secure!

He's not wrong though, your friend might have unrealistic ideas about how things could go in the future...you're the best person to judge that! If you think there's something there then you'd better talk about it sooner than later! I do think that's a special thing worth thinking about in this situation that makes it a little different from a different friendship.