Examples situations close friends of mine have experienced:
1. You are a PhD student and he (and it usually is a he) is your professor.
2. You are in a profession with limited opportunity (say, HR) and he is your boss.
3. You are an immigrant, and losing your job means leaving the country.
4. All of the above.
I feel articles like these are written by people that have never been in above situations. If you are in a dependency situation, you are fucked. Pro lifetip: Avoid dependency situations whenever you can. And sometimes you can't and just have to hope for the best.
(edit: add styling)