I can answer the question about why he stayed with Jones so long. Jones told him and he believed it that he wouldn't be able to find employment anywhere else.
I mentioned this earlier with Trump supporters and why they won't ever leave him. It's a cult thing. Even as part of you is questioning everything that's happening, maybe even flat out knowing it's not right, you stay because you are convinced that leaving would be worse. For him he's convinced that he'd never be able to get another job. If you need to work to live and you are convinced that you could never work anywhere else, it's an extremely strong incentive to stay put and swallow all your doubts.
This is similar to Trump supporters. Except for them it's not so much the fear of never being able to work elsewhere. It's the fear of basically admit they where stupid and having people forever think of them as stupid.
It's easier to advocate for stupid and evil things and convince yourself that it's totally legit than it is to go out and admit to others you where stupid.
You can say that stupid stuff that you secretly doubt but stay in denial and convince yourself you are smart. But once you cross that line, say you where wrong and admit the stupidity of what you previously defended, there is no longer any defense. And you have to stand before the slings and arrows of other people's criticisms and just take it. Whereas before you could have just smugly called them a snowflake libtard and convinced yourself of your own superiority.
For the record abusive romantic partners almost always try to convince the person they abuse that they would never be able to find another partner. This sort of behavior is a strong calling card of abusive personalities. Unfortunately it often works.
