I can totally relate to you regarding your W's fantasy thoughts about how S/D will look. We attended a NYE party w all of our friends (of course most of them don't yet know we are S).
HE comes and goes to our home & makes himself as comfy as he always has---goes in our hot tub, takes a shower, eats whatever he wants, does the laundry, etc. It is weird that he thinks this is what will continue.
This is where we as LBS have to decide and make our boundaries clear to our WASs. My problem is I don't know what I want in some cases. I agree that it may have to do with the friendship thing (as that's what my H has indicated he wants too).
Unfortunately 90% of our friends are mutual and 99% are married, so that means that one of us may end up with very few friends to socialize with.
My H also wants to be "responsible" even though he left, as to lessen his guilt for leaving and not dropping the ball on his responsibility to his family (what a joke considering he left)!
I agree our Ss are living in a fantasy world! OP is part of that.
M- 18 T-21 S-14,11 & 10 BD 6-18-2012 (OW-EA) H moved out 11-3-2012 10-5-13 Me- I want a divorce. I want to move on w my life. 11-25-13 Jointly filed.