Bob Dylan - You're Gonna Make Me Lonesome When You Go Lyrics Meaning

Saw someone he likes, better than his shallow relationships and one night stands. Slowing him down, causing him to be self reflecting and maybe being hooked on this red head.

It gets more confusing then.

Is it someone who is terminally ill, and he will see him/her in the faces of the people in his travels? How else would he know they're leaving now? To be remembered in the sky?

This would explain the refrain:
"You're gonna make me lonesome when you go.