Masha and TK's affair (all the stuff going behind Sasha's back) was called off by TK and TKW. During their last visit TK paid almost no attention to Masha even though she begged for it (through actions not words) and it really got to Masha
They were not in an open marriage until recently and that was the first time she's had sex to two men at the same time. It seems as I listen to them argue right now that Sam is tired of Eva and doesn't care if he hurts her or if she leaves or stays.
I can confirm Baldy does have feelings... after they finish he said that if she wasn't married he would fall in love with her she whispers something back in his ear. They never had sex before and the entire situation was un planned for him.