I'm sorry to hear about your loneliness.

Do you think perhaps your being lonely might be linked to a stubborness to accept people for who they are?

So just what would be so bad about lowering your standards a little? You may just find a diamond in the rough. Is it that you feel a need that as a couple you must appear to be better than average? I sense you feel a need to draw the attention of people and hence any relationship must pass scrutiny. I think if you lightened up a bit you may actually find it easier to get what you want.