Quick answer to your first question, it sounds like your H is quite deep in depression. Like... pit of hell kinda deep... and sounds like it's been from the start. Otherwise, he sounds like he's still in replay.
Before getting too much into anything, have your read Divorce Remedy? Really a good idea as that is the basis for how we approach M breakdowns.
Cadet should be along with his list of reading material, although it sounds like you've done your share of research.
I think your H, or at least your description of his behaviours, the "start", etc, is a really good example of MLC.
You do not talk about how things were between the two of you prior to his drastic changes except to mention he cheated on you, once before. So I would assume that for the most part, he was a "good guy" who you loved and presumed about as normal as people get...
and then he "snapped"... and people really don't just "snap"...
Now I do want to point out right now, and like I said, read DR, is that your own behaviours and language are likely not helping the sitch much. No, we can not fix them... we CAN make things worse, though. We can actually induce a stall in stage if we are confrontational and engage in the types of blow outs you've described the two of you have had...
So, you really do need to step back and take some really deep breaths...
More will come along to support you in your sitch. Post frequently (ie. a couple times a day) and it will help get you off moderation.
And a word of advice about this forum. Try to use more formal structure and keep the post entries shorter. It helps others read the content and support you better on item by item stuff.
