Welcome. I'm far from an expert but I'd say you need to see a doctor and a therapist. You have way too much to deal with for one person to bear.
You may benefit from antidepressants, and you really need someone to talk to. You are not alone anymore. There are a lot of nice people on this forum who can help you.
There is nothing wrong with needing some help and you are not a failure. You are strong enough to pull yourself away from the drinking and negative people so give yourself a pat on the back for that, that is not easy!
As to where to start? You already have by posting here. Next step is make a couple appointments. One with a doctor for a physical and perhaps antidepressants. One with a therapist.
Keep in mind that you are NOT a failure.
Chronic pain, Depression, Fibromyalgia, Tennis Elbow (both arms), Arthritis (knees and fingers), Diabetes. Ruptured disk L-4, Severe degenerative damage L5-S1, ACDF C6-C7