Agree with everyone -- H does not get to stay at your house, and H does not get to renegotiate his support settlement with you -- period.
Enforce that like your life depended on it. When H leaves, his problems are his problems and you are no longer obligated to help.
Detaching lovingly does not mean giving in on things like this -- it means truly feeling badly for him that he made decisions leading to having no money and having to live with his parents. You're sorry for how he is feeling, you understand that must be difficult, but you are not responsible to fix it. That doesn't make you heartless or guilty of anything. You went to court, you made an agreement, now you will *both* live by it, not just you.
Accuray
Married 18, Together 20, Now Divorced M: 48, W: 50, D: 18, S: 16, D: 12 Bomb Dropped (EA, D): 7/13/11 Start Reconcile: 8/15/11 Bomb Dropped (EA, D): 5/1/2014 (Divorced) In a New Relationship: 3/2015