It sounds like you are really doing the best things that you can for S. It's hard to let go (I can't even imagine that right now), but for the good or bad, H is S's father, and you have to give that R a chance (which you definitely are). I hope you were able to enjoy your time to yourself (and get some sleep!) and hopefully too, H can gain a greater respect and appreciation of what you do for S everyday (ie, waking up early). I think you are definitely in the right to set some boundaries though about what conditions must be met for S to sleep over. You could do something like once a month at his parent's house for now to get S accustomed to sleeping over with H (which is how is life is going to go), but state that no permanent arrangements (like every other weekend) can be made until he establishes a permanent residence and a personal space for S. That is completely reasonable and not at all mean.
I understand your reservations though. It's hard when you doubt their moral character (regarding H), but the best thing you can do is just keep teaching S the right things and showing him how to live a good moral life. I believe that we as their moms and main caregivers, have alot more impact on their lives, despite what they experience around them. I see that even with my MIL w/ the lack of discipline given there, but despite it all, S is still turning out to be a reasonably well manner boy and he listens to (well, with in the realm of a 2 year old) and respects me.
Well, I hope you had a wonderful Christmas full of joy and family and are enjoying your time off! =)
Me 27; H 28; S 2 Togeth 9; M 4 Sep 11/14/08 EA OW1 Sep 08 EA OW2 Mar 09 EA OW3 Jun 10