doing this for a living must be hard on the mind.

Depends on the individual I guess, Old guy at my church was a undertaker for years, one of the funniest guys you will ever meet, and always jokes about it. His favorite joke is to tell people he's the last person that will ever put him down. I guess him joking around about it helps him cope with dealing with death every day. If you look at it as just as job, you'll never get through it. Look at it as a necessary position and instead of cleaning, you are doing the family a service in helping them cope with the loss of a loved one.