Betrayal operates on the very simple premise that awkward small talk is the same as chemistry. That, and there is no greater attraction than that of two lonely people. Their sob stories are common ones: Sara got married when she was young and trusted others' opinions more than her own, and Jack married the daughter of the family that took him in and raised him because he was too scared to break away.
I'm even sympathetic up to a certain point. Meeting someone new and attractive is a temptation. Coming from a marriage where you feel neglected because your husband is caught up in his job and is working to establish a political career probably makes it even more tempting. However, the one thing Betrayal failed to do was make Sara a sympathetic enough character that you feel on her side. It's like it's relying on a very niche audience of dissatisfied housewives who condone cheating. Maybe this target audience is larger than I think; however, I'll be shocked if Betrayal lasts.
It's the lack of sympathy that really makes me mad. I have successfully been sympathetic to serial killers; it's not that hard to get me invested in morally dubious characters. However, Sara's almost clinical choice to have an affair is just cold. Yes, her husband is ambitious and distracted, but she hasn't gone above and beyond to fix her marriage, either. I have even less sympathy for Jack, whose only real complaint about his life is that his "world is small." There are other ways to broaden it, Jack. I'm sure Buzzfeed has a top 30 list somewhere that can help you out.
The only thing that made sense from the whole show was when Jack's vaguely nefarious boss/father-in-law's reaction to Uncle Lou lying to him. In a distinctly Godfather-ish voice, he foreboding growls, "After the first betrayal, there is no other." Melodrama aside, he's right. As the ever wise Chuck Klosterman said, "[Cheating is] not about physical contact or emotional intimacy; it begins the moment anyone decides that it's unreasonable to be sexually committed to one person."
Betrayal contributes nothing good but romanticizes everything about cheating.
I hope the Cancellation Gods have my back on this one.