Interestingly enough D is has spoke to me before about suicide rates, especially those rates with kids that are adopted, and double whammied by divorce. You are also right that he desperately wants her approval. He will just randomly walk up to her and just say "I love you mom".
I agree and I have told her the same thing. Get him into anything as long as he can socialize and make friends. I think she wants him to play sports especially with her concerns about him and his weight. In her mind he wouldn't do anything if she let him have a choice that he would just sit there on his ipad all day. Honestly I have experience with that because when he has been with me and ask him to go outside to play he wants nothing to with it.
She does have high expectations. There have also been times where she has flat out told me that she wants my input because her mind doesn't always think right. She is very driven, pushed hard herself by her mom, and obviously had to work very diligently to become a doc.
My hope is that I can help balance her out in a positive way whether this leads to marriage or just a long term relationship. Maybe at minimum I have opened her eyes to a different way that could just be as equally successful.