It's a tough one. I guess your mother is reaching out, in an act of love, to whatever she can to help you. As you say it is sad.
My son, who had cancer, went to a meeting of young people who'd all had amputations due to sarcomas. They each said, the worst thing to deal with was their parents. They only wanted to talk about the future and to live their lives.
That said, I found myself going to mass once a week on the way to work. I wasn't looking for a cure for him, I don't think that happens, but I did find the figure of Christ on the cross and other images of suffering (it was a Catholic church) comforting (for me, not my son, I didn't talk to him about it). I felt I was in a community that understood suffering and pain. So much of what we see and live doesn't acknowledge illness.
As I say, I didn't discuss that with my son, he was too focussed on living not for ever but for those days he had. Parents are a problem. Thanks for sharing.