For around two years, I worked with someone whose behaviour was very sub-optimal on many levels. She was evasive, confusing, discouraging, downright dishonest on several occasions. She also made a series of suggestions in relation to the projects we were jointly involved in that were, to put it mildly, completely stupid and would have ruined everything we were working on if she’d been allowed to have her way. (Might this all be just my subjective opinion? Perhaps, but I don’t think so, and in any case that’s not the point of this question!)
I was then approached by somebody higher up who asked me if everything was going okay because they were worried about what they’ve seen this colleague doing. I told them my concerns, and that person instantly removed my colleague from our project, and said she would work on it with me directly herself instead. Since then, everything has been absolutely fine and gone really well.
Then yesterday, I received a message from the original colleague, saying that she was very sorry to hear that I felt it hadn’t worked out when the two of us had worked together and that she’d be very open to receiving feedback so that she could take it on board. In other words, she’s asking me: ‘What did I do wrong?’
I don’t want to be dishonest, and I’m actually quite willing to send her an email explaining why I felt I could no longer work with her. However I don’t see much point in doing it in a tactful ‘Oh, there were just a few communication issues!’ kind of way. It might be useful for her to have my true feedback (she might then at least learn that she can’t lie and be so terrible at her job and expect to get away with it) but the problem is that my true feedback would be an itemised list of around 20 things - and would, I’m guessing, be pretty devastating for her to read.
Am I being unreasonable (or just unnecessarily mean/cruel) if I write back and tell her honestly all the reasons why I no longer wanted to work with her?
NB - some of you might be thinking that the higher up person should be the one to give the feedback. Perhaps that’s the case, but she hasn’t and won’t. So please treat my question as applying to a situation where, basically, it’s going to be my feedback, or no feedback. Thank you!