If you are religious and are living a comfortable life and your family is safe and healthy it is easy to believe God is good and watching over you. People who have endured tragedy or encountered the seeming indifference of God to suffering that slip out of the Christian camp in the middle of the night. Why worship a God that visits us with such suffering and loss? I myself was furious with God for the cruel lingering death of my mom. It's far easier to just be an atheist rather than walking around wanting to punch God right in the face.
My mom had a lingering death as well, so please accept my empathy and my condolences, even if it has been a long time.
Blaming God for pain and sorrow is fair if He is credited equally for pleasure and joy. I've looked at it as God was never here to protect us from pain and sadness, because it is not a question of whether if we will suffer but how we will suffer. This part and parcel of human existence in the physical realm, and God is on hand, not to protect, but to simply be with us as we make our way through it. I too (as do most) know what it is like to hurt so badly all that is wanted is to be left alone, even from God. At least for a time.
I do not blame God for the pain and suffering that is part of the physical realm of existence. Genesis tells us that Adam (the name means mankind) chose this existence, and woman encouraged this choice. Mankind wanted to experience the bad with the good, that knowledge of good and evil. It appears God advised against this, but when the choice was made He promised to stay close.