Mental stability evaluation

I don’t know how to ask this without sounding mean, but I’m really not trying to be mean about this…
My fiance and I are going through a custody battle with his ex and she is starting to get very ugly (not allowing him to see their child and all kinds of stuff). In the past his ex was on medication perscribed for depression. If you know her well at all you know that she isn’t exactly the most stable (mentally) person you’ve ever met. Her mother has manic depression (or bi-polar disorder) and so does her grandmother; I personally think she has it too, but she has never been diagnosed with it. She refuses to take her medication that the doctor perscribed years ago for her. I want to know if there is any way for us to request that she be evaluated or something to see if she has this condition like the other people in her family do, and if there’s anything we can do about it if she won’t go to the evaluation? We don’t want to bring it up to embarrass or hurt her, but we (my fiance and myself) feel that if she were “in her right mind” she wouldn’t be doing all that she is doing to him and their son.
Thanks for your help!

You can request a psychological evaluation by filing a motion with the court for the same.