Their ego is hurt
The male ego can be quite fragile. Don’t let all of that huffing and puffing fool you. It’d odd and sad because, when a woman’s male partner becomes successful, she doesn’t start to look inward and say, “Uh oh. This makes me look bad.” No way! She’s typically just proud of her partner. But in the reverse situation, the man can think his partner’s success makes him look bad.