This is tough for me because I’m down for the concept of an unreliable narrator, but those details were pretty … detailed. And it seems like a lot to swallow that Claire is making up interactions with all those mistresses.
I read those incidents as perceived slights in Claire’s eyes. I think part of her wanted to know Frank was being loved and cared for in the way that she couldn’t give him. She’s also projecting her guilt on others, and perhaps leveling the playing field by assuming Frank “cheated” just as she did. (That’s what I think Claire is thinking, I don’t see her marriage to Jamie as cheating in the strict sense of the word.)
Anyway, so did Frank have an obligation to abide by wedding vows he made before his wife disappeared for three years and came back pregnant with another man’s child? Legally, I would say yes. But ethically? Morally? Clearly, Claire expected him to. But did she stick to her vows, really? After she returned, I mean. Legally, yes. But morally or ethically?
Claire says she tried to make him leave, but he insisted that he would not abandon a pregnant woman. I give Frank a lot of credit here. What was he doing for the 2-3 years of Claire’s disappearance? Had she been legally declared dead, giving way for him to marry another woman? Or did he pine for her that entire time as well? I have no doubt that Frank truly cared for Claire and was frustrated and extremely hurt that she didn’t have the same love for him prior to her disappearance.
I don’t condone cheating either (I’ve been there too and it’s devastating and a senseless selfish act that hurts those who typically don’t deserve to be hurt). I have an issue with reconciling “cheating” Frank with the one who continues to show himself as loyal and protective.