how to cop?

Bro I stopped self-harming a while ago, but today when I was In my room trying to study my mom suddenly came in. Slapping me, calling me names.

And forcing the idea of religion on me, saying she's better than just because she's religious more than I am (I am literally an atheist but whatever, I can't tell my parents because they'd abuse me even more)

So, what happened today triggered me but I am trying to resist :(

I feel so caged in and helpless, what can I do?.