302: Abused/Battered women, Obsessed with a competitor, Overpopulation & Mental health

In today's episode, Dr. Lisle and Dr. Howk discuss the following listener questions:

1. How do you square the notion that there is "no 1 mate" (or job, friend etc) with the jealousy/abuse/ stalking (and worse) that happens in relationships. What type of general education on this concept could be offered to attempt to mitigate such costly stone age behavior. Related, can u talk about the treatment of battered women in your practice, how they do or don't escape? Buss claims one contributing cause of such behavior is patriarchal culture and institutionalized male dominance. Any truth to that or is this just genetic like everything else?
2. I have a frenemy (that is, a friend who was really an enemy) who I've long lost touch with, but whom I still irresistibly stalk on social media. She was very competitive with me in college, although I drastically outperformed her at the time (I was the dux and she was upper-middling). Nevertheless, she went on to similar feats as me, getting her PhD from Yale (again, the same as me). I see her subtweeting things about me occasionally and I wonder why, after not being friends for so long, we both harbour a malevolent obsession about each other? What is the evolutionary good of this? Neither of us stands to gain anything from this and we've both achieved what we wanted, showing that it wasn't the zero-sum game we might've thought during our early college years. She has become a tenure-track professor while I started a very successful company and am now a millionaire. Why do we ruminate so much about enemies/frenemies, and how can be finally move on from them?
3. I was wondering what over population does to a society. I understand nothing is changing genetically but was curious how lived experiences differ between populated densely packed cities and villages/ towns. Is one better than the other for mental health?