You are not a failure. You are hurting. I'm glad your mother is trying to help you. So you have tried zoloft. I have tried many types of antidepressants. Just telling you my own experience. Some did help enough to lift me out of the depression for a while. It wasn't meant to be long term solution for me.
Side effects are awful in my opinion, but sometimes it will take about 4 weeks or longer for your body to accept the medication. It is an option. So is what your mother is trying to help you with. I can see that being a heavy feeling. Been there. Been blamed, still don't know what to think. I know I have had to forgive myself and ask for forgiveness, and move on despite my failures