Women are selling out men because its in their nature.

Partially to do with hypergamy.

Women are never satisfied.Its in their nature.

Most women, when they get the impression that they can do better somewhere else thats where they will be looking.

The feminist notion of men trading a 40 for two 20s is projection .

https://en.wikipedia.org/wiki/I_would_rather_cry_in_a_BMW

I suspect that this has been part of what has driven civilization .

But the female mate selection process can become dysfunctional.

https://en.wikipedia.org/wiki/Fisherian_runaway

At the same time our given selection process is woefully inadequate and uninformed .