“He was looking at me too.” I’d mentioned to my friend that a man in a bar was checking me out and I instantly regretted it. I was 28 at the time, and nights out were rarer than they used to be, so I was hoping to avoid the competitiveness. After accidentally triggering it, and feeling embarrassed about making an offhand comment, I had to ask myself serious questions about this friendship. There had been a group of four of us, and it had been this way for over a decade. The competitiveness...