You asked what we think...
I would encourage you to read through my past posts. I was on a similar rollercoaster. I had a restraining order against my ex and was holding all the cards, just like you. Then I found out what I had always suspected- that he was having an affair. I was so upset that I let this cloud my judgment. Suddenly it became all about, "She can't have him." I dropped the restraining order and let him back into our lives. BIG MISTAKE.
Now, looking at your post my first impression was that you write this out as if it's some kind of dramatic chapter book. You even have names for the different chapters. Could it be, that on some level, you are excited by the ups and downs? Looking back, I can definitely say that was the case for me. I was addicted to the high that always came after the storm. This was when my ex would be the perfect man. He'd shower me with compliments and tell me he was willing to do anything to make things right. He'd cry and tell me I was the best thing that ever happened to him and that he couldn't live without me. Sure felt good. But it was all fake.
You say you've been seeing him curled up in the fetal position, working through the pain. And yet you say that he's been completely sober for5 months, and that before that he was only smoking weed, right? Percocet withdrawal is supposed to clear up in no more than days, so... hmmm... all I can say is this sounds quite a bit like the "flu" my ex used to get quite often, that always seemed to resolve itself after a quick trip to the "store".
Please do start attending face-to-face meetings for support. You need to speak with people who have been in your shoes.
I had so many people telling me to leave my ex, but it never quite sunk in until I went to a meeting. Those ladies didn't have to say a word- it was written all over their faces. I looked around and realize, "Wow. This is bad."
All the best to you. Please keep posting.