I really feel for you and can relate to a lot of what you are going through. Please know that you are heroic for doing all that you do. None of what you are struggling with is easy, and I can tell from what you wrote that each day takes so much courage and strength.
I feel the same way you do about the social aspect of life. I am around your age and on some days I just feel like my life is over, with seemingly no hope or fun or anything to look forward to on the horizon.
I wish you the best and hope you can be gentle with yourself. Loneliness and depression and the daily grind are so hard, but we can be friends to ourselves by treating ourselves with compassion and by being proud of everything we are able to do on a daily basis, no matter how small or mundane they might seem.