My H has been in this tunnel for 6 yrs. It's been tough on all of us (3 sons). His behavior can be very erratic. I noticed a real change when his mom died. This was followed by his sister moving her family in with Pop, and the whole sibling thing started again. Sister was the "princess". There are probably as amny "triggers" as there are people. We've been the whole route, and I thought were on track. Not so, we live apart. He has been calling alot lately, for any excuse. The sons (21,23,25) have decided to talk to him about counseling. He has gone in the past, but when they want to meet the wife, all the lies come out. Patience is something I have had to learn. He had a great job, salary, etc. You are right, they certainly do preceive things differently.
When you can't make a decision because you are torn between your heart and your head, listen to the half with the brain.