Maybe not relationships specifically.. but more like a person of the opposite sex who has caught your eye. How much do they effect your work?
I've noticed whenever there is no girl I am currently interested in, i draw a lot of male demonic characters. But as soon as I get involved with a girl, i start drawing a lot angelic female characters.
This also effects my use of color, as when without a girl I draw darker more black/blue and black/red, while when involved with i draw more white/blue and the like.
Just makes me wonder how many factors shuffle into our creativity.