Aww FS- I can read your pain and frustration. Listen, I may be one of those people that has moved on quicker than you but you cannot compare our situations. It was so much easier for me to detach and then move on as a consequence. Heck, I haven't seen him since the 1st November, so that's a start. I've only exchanged 3 texts / emails (the last one telling to get his head out of his a**e and get the financials sorted)
It stands to reason that letting go will take longer with your situation. You are doing all the right things so if it is going to happen it will happen. I promise you when you're ready to let go / if you're ready, you'll know. You will wake up one day and know. If it's not the right time now that's not because of a 'fault' of yours. You're obviously a very rational person and perhaps you need to listen to your gut. I actually think that you have done a pretty good job of detaching but that detachment hasn't led you to move on. For me they were 2 distinct processes. There was no way I could move on without detachment, but I'm not sure that one always follows the other. For me, detachment is the means by which you receive clarity of thought; to stand or to go.
It must be heckish frustrating but I think you need to give yourself more time.