I can just tell you what I do.
Reaction to him buying me flowers: Whatever, and go about my business
Reaction to him buying a beer: whatever, and go about my business
Reaction to him passing out on the sofa: whatever, and go about my business
Reaction to him doing the dishes: whatever, and go about my business
It takes practice, but it works for me. And distancing yourself helps. I'm currently sleeping in the other room and it has done WONDERS.