Here’s some hard to swallow pills that’ll probably make people upset but is 100% the truth and idc.
You do not have to stay in a relationship with a mentally ill person if it becomes too much for you to handle. You are not their saviour, that’s not your responsibility to save them.
Any person who uses their mental instability to control you staying is a shitty person. IE “if you leave me I swear to god I’ll kill myself”, still not your responsibility, LEAVE.
That goes for friendships too. If it becomes too much, get out. Anyone who uses their mental state to guilt you into caring for them or staying is NOT someone who actually cares about you.