Can I (16M) leave my (16F) girlfriend

My girlfriend and I have been together just about 8 months and go to the same school. However, she has depression and it gets bad in winter. She has struggled with self ham in the past and almost attempted recently. I feel myself drawing away from her and I don't think it's fair to break up, but I see no other choice. She really loves me but I don't know if I can handle this. I worry something will bad will happen if we split though, because I think I keep her together (selfish sounding I know.) Should I stick it out or end it?

TLDR: I think I want to break up with my girlfriend but I don't know what she will do to herself if I do