It hurts. I know. I've been there in the howling isolation, the WHY ME? You are not alone in that experience.
This really is such a difficult Catch-22. How many of us have a hobby, or habit, of either dwelling on this icy irony or re-playing the failures of friendships lost? It can be quite addictive, and daily life seems to reinforce the theme over and over again.
There are no easy answers to this, probably no total "fixes" at all. This forum is positive because it is a first step in overcoming the terrible shame>invisibility>shame cycle. We are unique and for whatever reasons have taken on the role of "other" and feel outside the common circle.
What helps me: small, incremental things--the smallest warm interaction, whether by helping another or being open to the positive feeling (again, small in scale) that is in my environment.
Self-affirmation: knowing that as strange as things (and I) feel, I am a part of the Universe, I am part of the fabric of Reality. I Am Here.
Nature: fresh air, squirrels, the green gleam of my cat's eye, planting seeds, the night sky.
Cultivating my interests--reading, creative activities, listening to what inspires me (the inner Muse). Look, if you are never going to be one of the celebrated "normal" folks, why not develop your unique vision? We have a certain freedom that many others do not--by not being accepted, we have "nothing to lose" in becoming visionaries (or at least not credulous sheep).
Stoicism and Humor--this is a difficult burden to bear, as everyone reading this knows, but we must have been especially strong to have taken up its challenge. A sage once said that we are ultimately here on Earth to develop our Integrity. As outsiders, we are doing the advanced/AP version of this. challenge. The humor part is bit dark and bitter...sometimes laughing at myself, sometimes laughing at yet another situation gone really f*cked up (again! again!).
Sometimes, offering a sort of radical peace to the messed up situation we find ourselves in is helpful. Knowing on one level that we want things to be different, we want friends and connections. But perhaps on another, we can embrace and lovingly accept, however quietly, the reality of our lives just as they are right now. What if this is indeed "as good as it will get"--can we even for a few seconds find peace, acceptance, and kindness towards ourselves in that thought? If so, a new window of possibly will open within. Try it with me....
