The only term I could think of is defeminization.
It seems like most people understand what emasculation is and the things that cause it.
What are some examples of situations that can cause the feeling?
Edit: changed effeminization to defeminization.
A bit of a different take on this are the sworn virgins of Albania. They give up their femininity, reproductive and sexual identity and are treated as male in every way.
https://en.m.wikipedia.org/wiki/Balkan_sworn_virgins