My boyfriend said that my child is ruining Christmas

I found out that my 14 year old has been self harming. We ran into some issues at school because in the middle of the semester when he was changing in the locker room he was trying to keep to himself and a kid pointed out that he had a boner. So they started making fun of him and calling him gay. Then one kid told their parents and we had this whole thing where a parent was demanding my son change somewhere away from the population because they didn't want their son naked around a gay kid.

I've spoken to him about the incident and told him it didn't make him gay and he said he doesn't know what he is. Which I said he's in 8th grade and that's fine. Whether he is or isn't he's fine. We have had some bullying from children and these parents spreading rumors about him. So when I found out he was harming himself it broke my heart.

My boyfriend who I have two children with told me he's made the last few months sad with his moping around. I've put him in therapy to help but my boyfriend said he wants to have a good Christmas and my kid is ruining it. I just feel so helpless because I understand as a family, my boyfriend and our other kids don't deserve to feel sad but I'm also concerned about the self harming.