Welcome Fdxmusic,
self harm is one but not a necessary criteria. What matters is less the exact diagnose at the moment but taking concrete steps to stabilize and then improve on it.
You wrote that she has recently born a child. Sometimes hormones controlling pregnancy and later phases like breast feeding can impact emotions in a big way. How was your relationship before the preganancy?
I feel like she thinks I'm the wrist person on the planet.
She is right! ... .at least in her mind . Don't try to battle that perception with a frontal assault (which would be invalidating). You will just cause her to re-enforce her distorted thinking. Check out workshops on validation and SET on how to help her to deal with excessive negativity.
Every thing i do has her in mind.
This is the road to doom. Seriously. She causes drama. She is spinning and tumbling out of control. If you want to stabilize your family you need a reference frame that is grounded and stable. If all you do is focus on an unstable person and let that person guide you then you will make the problem not smaller but add your energy to make the problem larger.
I don't know how to suggest clinical help and the relationship appears to be coming to a close. All signs point to get moving back to her ex. Help!
You can't get her into therapy unless she wants it. Only she can change herself. One option may be to seek out help for yourself as such a relationship can be extremely draining and detrimental to your self esteem .
Again

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a0