I think this is your problem. Your goal is to
A) have your kid do well in school
B) get mentally healthy
What is the root cause of these problems? You state it very clearly in your third paragraph. NJ. My guess is that your kid wouldn't need a mental health professional if your X wasn't in the picture.
You're trying to treat the symptoms, not the cause. The cause of the problem is that your former wife is incapable of doing a half way decent job of parenting. The solution and your goal should be to get custody, but you're approaching the problem from a standpoint of trying to fix the symptoms.
Have you filed a petition for modification asking for primary custody? The significant change in circumstances is all of the above. Don't go into the hows or whys. Focus on what is. This is pretty simple in your case and relatively easy to present clear evidence on. Your former wife can't function as a parent. You can. Best interest shouldn't be too hard here.
Edit: I'm not advocating taking your X out of the picture. I'm saying your goal should be to take over the primary duties of being a parent so that her relationship with your kid can improve. Regular and continuing contact? Yes. Best taken on weekends, and summer. Like every other weekend.
I have to agree with you and maybe I'm apparently not conveying it that way.
Bubba Seal wrote:Km, I think it was Ron White who said "You cant fix stupid"
One of my Ron White sayings.