What is left or What was left?

The alien below, left during a walk along Larchwood, was a memento of a close friend of mine. It was acquired the second time we were out together from a 25 cent machine in the Wal-Mart. When I missed him greatly, while I was away and dealing with myself, I carried it in my pocket. I question "What is left" or "What was left" because I find him extremely difficult to contact and sometimes as almost a chore of a friend(which sounds terrible, but more explanation would make the statement more understandable). Therefore, was it just a memento left on a sidewalk corner, or is it all that is left of our friendship? I'd like to think the former rather than the latter. But the symbolism interests me.