Horrible ending
The initial premise was interesting and the initial chemistry between Scott and Westfeldt was almost believable, with a charming supporting cast... I bought the first part of the movie. Though the plot arc wasn't developed in the most realistic way, it's an interesting thought experiment.
At the end, the dialogue and chemistry really tanked. Something about the final pacing was off- Jason's change of heart was totally forced- the most pivotal exposition indicating to is that he intimates he had a "really" dirty dream about her to his sleezy friend at a bar?
The final scenes between Joe, Julie, and Jason were ridiculously forced. After a couple hours of watching other married couples fighting and a main character who chose physical attraction over his "best friend" for the first two years of their son's life, I mostly just feel sad. Don't think that was the point...