The second instance was a few years ago - I returned to uni and retrained. I had worked at a company for 6 years and my line manager changed - she criticised me, undermined me, wouldn't listen to my ideas, everything I wrote she rewrote because it wasn't her style. I gave up trying to challenge her, which she also didn't like. I would go home every night and cry. I called my profession's support line and said that I wanted to change roles but I was scared that I wouldn't be good enough to go anywhere else. They gave me enough of a confidence boost to start looking for a new role and when I found that I wasn't the problem.