My mom and dad have their own room, but they are old
Its because my mom snores and is up all the time (medical issues) and needs her bed super hard too.
I mean I guess if there are different issues it shouldn't be a huge deal because I know how ugly I can be if I'm not getting good sleep.
But I know what you mean...sometimes its just nice to have the whole bed to yourself!!!
When my babies were just born I slept on the couch for a week next to them. Hubby loved it !!!!! LOL
Maybe you could look into different mattress options for his back?????