I'm going to break up with my mentally-ill partner.
Are you sure that is something that you should do?
No, I just can't handle mentally ill people.
You should do what you need to stay healthy, but if you really love them, you should support them. Losing a relationship on top of the mental health issues could be devastating to them.
I'm doing what I need to do and I don't care.
I think that you should do what both of you need. I think that you can try to support someone through their mental illness without continuuing the relationship with them.