I see how he may have misunderstood about the other boyfriend. Maybe he was a long time, loved part of the family and important to the grandparents. Your bf is newer, you don’t live together, he’s not like a long time bf or husband.

You should do what you feel like doing and allow yourself to grieve. It feels to me like your mother, in asking that only you and your father be mentioned, knew your bf was not good…perhaps she helped you here.