I'm certain that the loneliness and isolation is crushing, I would have to admit to being at the other end of the spectrum, as I tend to crave solitude for the most part.
I also agree with you, the thoughts of being denied a life feels soul destroying, especially when it is taken for granted by the "normals". The only thing that I've found that eases the pain on that one a bit, is accepting the limitations of my ability to cope and trying to make the best of things within those perimeters.
Try not to think of yourself as a scrounger, none of us chose to be this way, also the damned fatigue that often accompanies mental health problems can be excruciating.
I guess to the outside world it makes us look lazy, but then again, the people who matter in our lives tend to be more understanding.
I hope that things start easing up for you soon,