Honestly, I agree with your IC. I went through a vicious custody battle with my ex some years ago. None of it my doing. My ex was trying to get me back for wanting a divorce. Once that was done, I made sure to be as flexible as possible with him about spending time with the kids and we have all benefited. Really,, the kids needs are most important. So I would say be flexible, have neutral expectations about your Hs conduct, and show both S and H by being a great model of how a wife/mother should comport herself. That would be my advice. It is generally better to be kind than to be right.