That's pretty cool actually. Most villains just go bitter and start plotting vengeance. Seeing one be discouraged after having his big plan foiled and deciding to rethink their life is something that should happen more often.

I know this reply might be late, but basically after the Infinity Gauntlet event Thanos was defeated and got turned down by Death again. As a result of those two things Thanos withdrew to a backwater world and took up farming as he rethought his life and tried to decide what he was going to do next.