Hi Pharm, Sorry you are here. Its sounds like you're feeling plenty of intense anxiety and many here know how hard it can be.
Some of the vets around here will likely have better advice than I, I just want to say that I can relate. My W is somewhat of an avoidant, and I'm anxious. You (anxious) and H (avoidant) have a similar dynamic which can get toxic when taken to the extremes. One of the links Cadet posted (pursuit and distance) can help explain the dynamic.
Many of us here are fixers. You may be as well. We want to fix the issues, fix the marriage and fix our partners feelings. This leads to control and desperation. We cant fix them, we cant control them. Do your best to understand that. Easier said than done as I revert back alot. You control one person, YOU.
Dont look for answers as to why he is broken. Its a waste of time many fall in to. What you want to do is fix YOU. Ive read that in pursuit/distance or anxious/avoidant relationships, as one spouse gets nearer to a secure baseline, the other spouse CAN become less extreme. No guarantees of course. Your goal is to do everything for you. Not H or the marriage. If you fix you, yes maybe he comes back, and if not, you are still better in your future life.
Self reflect on what actions and behaviors of yours contributed to this. 180 those behaviors and make them permanent. Feel your feelings, dont mask them. For anxiety, CBD oil, counseling, swimming and other exercises have helped.
His words and actions cut deep and I'm sorry, I know it hurts. What he is feeling is what he is feeling NOW. As you've seen, feelings can change. You're likely the brunt of all his feelings as it is easier to blame than to face them himself. Easier to avoid and be a victim. He may realize this, he may not. These things take a long time and patience is an asset.
Good luck Pharm.
H37, W37 D4, S2 ILYBNILWY 9/19 BD 9/19 EA discovered 10/19 Currently in limbo, no D or S process initiated