I am so sorry you are suffering. It’s one of the age old questions many have had over the centuries...why does God allow us to suffer? It’s a big question. He doesn’t promise any of us an easy life, but that doesn’t make his existence less real. Just because others have it worse, as you say, doesn’t mean your pain is less significant. God does care about your pain and suffering. You said you haven’t prayed in a long time. I would encourage you to start talking to God about it. Tell him specifically how it’s pained you, and ask him how he’s using it. I hope you discover some answers.