DP and I split for a year and reconciled this year.
In that time, I slept with someone who was a mutual friend of ours. After DP and I got back together, he was furious about what'd happened and says that if I so much as message/smile at him he would leave.
The man in questions son died a few years ago, I've always messaged on the anniversary just as a kind message to say I'm thinking of him. I messaged this time and DP went crazy. I think this is unreasonable given the weight of these circumstances but DP insists its wrong of me to even contact him.
AIBU?