sick

I’m so sorry you are feeling so down and I can’t pretend to have all of the answers for you. One thing I can tell you though is that you have to be kinder to yourself. From the way you express yourself I can see that you are an intelligent person and you really do not need to be talking about yourself like that.
You have to escape these melancholy thoughts and in my experience the best way to do that is to get busy and stay busy – so you don’t have time to think, about anything.
One thing you could do as a starting point is some kind of voluntary work. You would be helping other people which I am sure would help you too. You would also meet people. There are plenty of decent people in the world but you need to be in a position where you’re actually meeting them. It might be difficult at first but you would have to stick with it.