I can't help. There are too many.
I liked Slate's Magnum photo collection on solitude. I maybe shouldn't have clicked through their images of solitude. Seeing lonely people goes straight to the softest parts of me. I'm not worried about me, actually. I have lots of tolerance for solitude and am usually very happy daydreaming something while I walk or eat alone. I am not so scared of solitude for women, whom I trust to be able to break out of it (perhaps wrongly). But seeing men who look lonely just stabs me. Are they going to be OK? They aren't, I don't think. I get scared they don't have the words or the ways to reach for the friends that they need so bad.