GEL... I have learned to not get caught up in one bad interaction; you take the good with the bad and hopefully move forward. I'd probably let it drop, too, since you have that mini-vacation planned minus son...it's not a pass to let him off the hook, as you know.
I know with my H I can't be as directly seductive as I would like to be. Wearing a robe and perfume is really at the low end of overt seduction, but I could picture my H shutting down and passively ignoring me. What works for us is keeping an element of sexiness going throughout the day...a grab here, a kiss there, along with little discussions of when our next time to ML will be. That way, there's a little more spark in the air, and if there's still that roommate feeling, well, he knows what is expected.
In JJ anlaogy terms, I'm thinking you can drop a few bread crumbs, through verbal banter and little grabs, for him to follow the path to the candy house, all the while discussing what day to visit for sure.
As far as the selfish aspect, it sounds like passive-aggressive behavior due to your " ploy" and I'd drop it for now. He knows better.
