It's not really to do with mental ill health, it's to do with how effectively you communicate with others. If you have good interpersonal skills there's no need to fear a stable partner will not 'put up with you'. And if you don't have good interpersonal skills they can be learned.

But I think you're right that those with less than perfect backgrounds naturally attract the more 'f-ed up' types, and are attracted to the more 'f-ed up' types. I think that's just a natural 'being used to what you know' thing. Just as people tend to be attracted to those who remind them of their parents or remind them of home, people from less healthy backgrounds will also seek the familiar. If you're aware of it you can avoid it, though.