I was initially stumped by this one. “Alone” does not equal “lonely” — it can mean that “you alone” will be responsible for a task. Or it has the connotation of being isolated or set apart to do something that no one else can do. So in a fit of over-analysis, I didn’t have an image come to mind that worked.
I mulled it over all morning as I did a couple of errands and went to see my Spiritual Director. And it was only after I sat down in her office and looked out on the cityscape that I saw someone who was truly ALONE.

Do you see him? There’s a guy in a dog suit trying to get people to stop and buy something (mattresses? lunch? I don’t know!) He danced, waved and tried to engage the cars rushing by. I never noticed him. I sat through a light cycle waiting for the green arrow, and paid him no attention. A group of people walked by him, and ignored him.

That dude was ALONE.