First, the pain is now yours. R is hard work, but so is D, especially after a long M. You have to deal with the pain no matter what you choose to do - you can only go through it; you can't go around or away from it. The good part of that is that you can really go for what you want, 'cause every outcome sucks.
I don't read any whining at all. I understand you want things to be the way they seemed. That's just not possible - but it is possible for you to thrive and find joy again, with or without your H.
IMO, you have to heal yourself - most of that is processing the pain (grief, anger, fear) of being betrayed and figuring out what you want.
Your H has to heal himself, too - he needs to deal with his feelings like you do, plus he has to change so he doesn't betray anyone ever again.
If you both want R, you heal your M together.
I had done a good deal of therapy before D-Day, so I knew how to let my feelings flow pretty well, but I also did IC, because there were more and stronger feelings than I ever thought possible. If you can't let your feelings flow, I suggest trying IC - and don't discount meds, if the pain is too great, so that means an MD, hopefully a good psychiatrist (because they specialize in psycho-active drugs).
I didn't commit to R until I observed my W act consistently for R for 90 days.
Shirley Glass sets up a stage of 'working on the M' for people while they're deciding what outcome they want. In this stage, you do the things you'd do if you were in R and the things you'd do to make your decision. That may be the best approach for you now.
But the first thing you need to do, after taking care of your physical health, is to feel your feelings and let them go.
Check into the Healing Library (link in yellow box, upper left of SI pages) - you'll find a lot of useful stuff there.
Also, it sounds like you're doing the right things the right way. It may take a long time to process your pain, but you're setting yourself up to do what's necessary. The road is awful, but it will smooth out eventually.