I am a straight middle-aged woman. One of my closest friends just came out as a transman. I have been crying for 2 days and can barely eat or sleep because... I am scared that all of my friends will cancel me if I don't pretend to be happy for him.

Doesn't sound like any "middle-aged woman" I've ever encountered or known of. Middle age nowadays is defined as the period between 45 and 65, so it means people born from 1955 to 1975. This sounds like a post from someone who has grown up much more recently, and mainly on social media.

Most women in the 45-65 age bracket who were born between 1955 and 1975 have seen too much of life, and experienced too many hardships and heartbreaks, and have developed too much strength of spirit and resilience, as well as a sense of humor and perspective, to fall apart like this coz a friend has newly announced she's taking on a trendy "identity" - and coz they fear all their friends will now suddenly cancel them for not going along with the pretense. Most grownups in the middle-age bracket are capable of tolerating differences of opinion with/amongst their friends without "cancelling" them.

Also, most middle-aged women I've known, and now know, can't afford to spend 2 days crying and falling apart on account of one friend's mental health crisis coz middle-aged women usually have demanding jobs (often two jobs), children to raise and tend to, groceries to buy, meals to cook, houses to clean, etc as well as partners and elderly and disabled family members to take care of.