How is sending out nude photos to single women a joke.... Am I missing the punch line ?

If you are not happy or comfortable, with a relationship where your partner is sending out nudes to women, emailing ex's, coworkers, and single women on facebook, then that's all you need to know. That you are not ok with that behavior in your relationship, and that you have the right to be in a relationship where this isn't happening.

I agree he is disrespecting you, your relationship, and his relationship with his daughter. He shouldn't be asking his daughter why her mother doesn't love him. Even if he was doing this to mess with the ex's head, what does that say about him? He says he was doing it to hurt you, again what does that say about him?

I would also do what his ex has done and walk away. I'm sorry you are experiencing this, I know it's painful. You have to put yourself first here. Don't let Bipolar be an excuse either, many many Bipolar's do not act like this. I have Bipolar but it isn't an excuse to hurt others.