Why does Allah let some people suffer so much?

When will my suffering end? it's been long enough since I'm in emotional pain. I think suffering never ends for some people. My mother is a nicest human being anyone would ever meet on the Earth and Allah has tested her through out her life. First she got an abusive husband and because of him one by one all of my mother relatives deserted her. From her parents to her siblings to her cousins to her friends all left her. Why Allah gave her such a life? I think same is going to happen with me.