> "It may seem sad that, even after knowing each other very well for many years, we can’t predict each other better to avoid such destructive outcomes. But in fact this unpredictability seems essential to the process. If we each knew the other person’s exact limits, then we might try to push them right up to but not past their limits."

A very cold vision of love (or friendship)

> The man initiates the break, and while he has several complaints, his biggest seems to be that she’s become too reluctant to have sex.

Tell me about it. At the same time she is slowly losing her youthful beauty, she is withdrawing from sexual activities, making it really hard for men to think their marriage is still a good proposition. Seems to happen a lot. What can one do about that other than follow the cliché and try to change a 40yo wife for two 20yo?

It's more biologically-rational to have as many marriages with fertile women as possible.

It's economically-rational to avoid community property states.

If limits are continually being tested, is it a healthy relationship in the first place?

yeah, i don’t think a healthy rewarding relationship— either friendship or romantic — is likely to be based on extraction of maximum value from the other person.

People can't help but compare.

Why do so many people seem to think that there is so much to be learned from fiction? I don't know what Hanson's qualifications are, but psychologists and philosophers always seem to be champing at the bit to demonstrate fundamental truths about real life from something that isn't real life. Are we all still stuck on Freud and Jung?

You can learn a lot from fiction. Sometimes fiction simplifies a complex scenario to illustrate an important lesson. Fables or children's stories are examples. Sometimes fiction shows you a complex scenario from different perspectives so that you can consider it without living it. That seems to be Robin's take here. To the extent that the scenario is "realistic" it's useful to learn from.