I'm sorry you find yourself here. This board is a wealth of support and encouragement.
In regards to your h coming over and wearing his ring, I will be blunt. I wouldn't read too much into anything at this point. The reality is that it will get better and is probably a bit less stressful without him being there. I would also skip any questions unless it has to do with logistics.
You are correct. There is a good chance there is someone else and I wouldn't worry too much about her. She has her own issues.
Read all that you can and come her to vent. Protect yourself and the kids and detach. Leave your h alone:)
3 kids BD 12/15/13 (IDKIILY. ) Rope dropped Cirque du Soleil style D final 9-9-14 "Some people are born on 3rd base and go through life thinking they hit a triple." Barry Switzer