I think I went through something similar when my Dad died (of lymphoma, five years ago - I'm sorry about your Mom).My mother recently died from leukemia. During the time while she was in the hospital and during the days up to and including her wake. I had many relatives go on about praying and heaven and so forth. In the end the sad situation if anything, reinforced my stance. There was something deeply insulting about people around me then going on with fictions instead of honoring her life.
People would tell me that they'd be praying for him. I couldn't help but interpret that as "I'm not going to do anything to actually help, but I will do something to make myself feel a bit better."
I understand why Robert Ingersoll (I think it was Ingersoll) responded to "I'll pray for you" with "I forgive you".