Sent a text in the middle of the night saying, for what it's worth, it's a real shame that he's lost me and such a waste.
They're abroad, at a place we used to go to, visiting the same things we used to, having a grand old time.
Seriously OP he's a GRADE A CUNT.
He wants to keep you on the back burner by making you think he has a grain of remorse about what he has done and he's really sad to have lost you. He doesn't give a fuck about you (sorry to say), he only cares about himself, getting his dick wet and flaunting his new arm candy on social media.
It sounds like you know the real him, and from what you have said about his issues this is all a bravado, giving the SM world the impression he has the best life possible while inside he is falling apart (and if he's got a drink problem he probably won't be able to keep it together for very much longer given his age anyway).
I know you said your support network is lacking, but do you really want this arsehole to be your support? He doesn't care and (as much as you say you don't) you can't treat him as someone other than someone you loved and wanted a life with. Cut off all ties and the friends who are supporting you, cherish them and spend time with them.
It will get better.
YOU DO NOT NEED THIS CUNTWAFFLE