He started feeling so when Lisa turned her back. I don't understand Russian, but if Lisa wanted to have sex with him, or interested in him, she would have asked him what is going on right now. Strange
I thought that Dean spoke about it with that guy. May be that is the reason he didn't want to have sex with Lisa that night although lisa did everything.
Another thing i noticed is that Lisa seems to be on russian Tinder.
I don't think there's any problem between Bree and Dean otherwise they would not be talking like good friends in the kitchen. May be they have resolved their differences.