I guess whether or not I let him move back would depend on his behaviors and whether there is some reason why you would rather not let him back into your house. If there are things he's done that you feel he does need to deal with on his own, then it would be ok for you to say "you're an adult, figure it out". BUT if he's just broken up and there's nothing "bad" going on, its alright to let him stay with you until he works things out. I had a similar thing happen to me where I had a bf I moved to a far away state with. When we broke up 4 years later, I moved back to my home town and did stay with my mom for a short, short bit. I got a job like the 2nd day I was back and moved out in less than 3 weeks. If you are worried he will not try to get work I would give him clear rules and stick by them.