Care and Feeding: How to deal with a competitive best friend?

Dear Care and Feeding, I'm looking for advice on how to deal with my competitive best friend.

She has an 18-month-old son who, in her mind, is incredibly advanced.

She often compares him to my brother’s daughter, who she knows has always been very advanced for her age, and fishes for compliments that they are similar.

The split was complicated but not nasty, but I caught him in an affair.

He expressed his desire for a freer life with less responsibility, to party more, and basically the need to escape the pressures of reality.

In the year that's passed, he’s only visited with our son for very short stints (about 6 hours at a time), and only every 4-6 weeks or so.

I’m torn over whether this is good for my son or not.

A divorced mother of a 7-year-old daughter was hurt by her partner's ex-wife's behavior.

" Sensitive Snowflake Stepmom " is not a "snowflake" by any means.

"You shouldn't consider staying just because this dude isn’t abusing you, cheating on you, or suffering from substance abuse issues".