Hi vanfam, I'd say that it was time to give him the ultimatum of getting help (and you can support him in finding it if needed) or you leaving the relationship/marriage.........do you think??
It sounds like it's not getting any better, in fact you said it had worsened...........and a genuinely loving/supportive relationship/marriage doesn't include a lack of trust and accusations (daily!!), this is sounding more like an emotionally abuse relationship/marriage more than anything else.
It really is great that you are understanding about his past and want to support him.........and if he was recognising the need/wanting/trying to take steps, and getting help in resolving things then sure I can see how it might be "mutually beneficial" in you sticking by him/supporting him/being there for him.........but he isn't is he? And you have got to think about yourself too in all of this, and you don't deserve to be treated this way.

Alison