I can't say much else, but I would firmly advise that your fiance not do anything that makes him uncomfortable. Friendship is supposed to incorporate mutual respect, including for each other's boundaries. Your fiancé shouldn't feel like he needs to do anything as an "obligation."
A lot of this I'm seeing as needing of communication, not involving you for the most part. I can specify more if need be. Can't at the moment.
Above all else, I do think your fiance and you should seek help from sources that aren't on an online forum like this one, where anyone can respond. Regardless, I wish you two luck.
