Terry,
One thing you said about sometimes a step or action triggers an unexpected reaction is so true!
I have SOOO moved on past my ex husband, however, rather recently I found out they took a vacation that he and I had planned for years, and years, he took it with her, but with me we just never had time. It actually really bothered me.
It just seemed that he is living the exact same life with her that we planned and my life is so completely different from that life. It's like she's me, only younger without kids, and it's just strange how that affected me.
I don't think it means I haven't moved on, or I wish him ill, but it just means I need to work on myself more maybe.