Pain so deep it bellows

If it helps at all, you’re not alone in your pain.

You say can’t leave him — is there anything you can do to start quietly planning/preparing to exit? At the very least, can you start the process of emotionally distancing yourself from him? Change your routine, start doing things you like, with people you like? As much as you can, start making a life for yourself and building a supportive social network. The more you do now, the easier it will be to eventually take that final step of breaking away from him.

I know how heartbreaking this is, but your fiance is not the wonderful person he may once have been. He’s being an emotionally abusive shit, from the sounds of it, and it’s going to eat you alive if you let it. (I’m not judging you – I’m in a similar situation). Do whatever you need to to prepare first, but when the time is right I hope you can summon the strength to leave him. The sooner the better, for your sake.