You should leave it be. I'm sorry, you missed your chance, and you shouldn't make that his (or his fiancee's) problem. When you think about it (and I'm not trying to be mean here), you are really only thinking of yourself in this situation. What are you hoping to get from this? To have him reciprocate your feelings?

Like I said, this is stirring up trouble. He's ENGAGED. That means he's off limits, and if you care about him, try to be happy for him and direct your feelings for him into ones of friendship. Good luck.

__________________
Live as if you were to die tomorrow. Learn as if you were to live forever. - Mohandas Gandhi