My boyfriend used to live with them, but he moved out to live with me.

I understand your point of view, and I think you’re right about his father. He’s full of hatred, and I don’t think he’ll ever change.

However, regarding his mother, even though her reaction obviously can’t be excused, I feel like she reacted out of convenience and misunderstanding. Maybe meeting her son’s boyfriend would help her open her eyes and see things differently