@TooOldForThis67 I think the self-sabotage is probably a (completely useless) tactic to try to avoid being hurt. You find someone (almost) perfect - or just really great - and you start worrying that he can’t really be that great or he wouldn’t like you etc. It probably gets more and more tempting to do this the longer you’ve been looking.
I have had moments of this bullshit with MrSG. I was actually pretty good in the beginning - just going with things. But sometimes I’ve had to have a word with myself about overthinking things and being stupid. He is pretty much perfect (for me, rather than objectively) and everything is just lovely with us so I should never let the doubts creep in, especially as they’re always doubts about me rather than him.
I read a book once where one of the characters claimed that they could trust themselves. I thought that was weird, because if I’m going to be untrusting, it’ll pretty much always be me that I doubt rather than anyone else.
I agree that, practically, in your situation stopping contact with MrWow is the best thing to do. How dare he tell you he loves you and then backtrack. What a mindfucker.