PTF I am sorry for your situation. After reading your thread I guess all I can share is something an old timer with almost 40 years told me. I probably will not get this quite right but he said something like this.
I have sponsored over 100 people in AA. Most of them failed to stay sober and others did not like my personality. So now I go in to a sponsor/sponsee relationship with the expectation that there is less than a 10% chance that the relationship will last long term.
I guess like you he learned this the hard way. Also the old timer did not stop sponsoring folks, he just adjusted his expectations.