If it was me, I wouldn't leave it in his hands – I would take control of it and tell him goodbye and not contact him again. But I like feeling like I have autonomy over myself and I hate having to wait to see what I do based on what someone else does. I would simply end it and go away. If I thought it would make me feel better, I would write a letter telling them their list of mistakes, but it doesn't sound like that that would make you feel better and I would send it by hard mail not email