A year and a half ago I broke up with my ex. He had a tonne of issues and not small ones. One of these issues happens to be that he is very insecure and possessive. It was a real problem. It was a little scary in the end if I'm being completely honest. Anyways, I ended things, cut all ties and got the hell out of there. I've gone a year and a half with no contact. I've even moved on. Lately he's been messaging me to try again, He's been messaging my family to find out if I'm seeing anybody. How do I get rid of this guy for good. I don't want to keep having conversations with him about us. I just want him to move on. Maybe find somebody who will have the patience to help him work on all his problems.
Unfortunately there isn't much you can do to help him move on. I assume you have heard his side of stories and you have told him why a relationship wasn't going to work? Other than that, there no option other than going no contact with him again, block or whatever, and tell your family to do the same too.
Worst case scenario, tell him it's harrassment and if it doesn't stop you will press charges. Sorry man. :/ (Also, Guelph!! My Nana lives there!)
Unfortunately...I had an ex who was very similar to your ex. Throughout the years...he would go to the extremes to find out my contact information. Many times...I would happen to run into him on the street or while running errands. What always puzzled me about his behavior is that he would actually think that things could resume right where they left off with us and there was no need for change within our relationship no matter how long we have not been together. Needless to say...this did not stop me or provoke me from not moving on with my life. Furthermore...I did have to obtain a restraining order to keep him away from me. At the end of the day...His growth is entirely up to him...not you...therefore...keep doing you and pay him no mind...sooner or later ...he will have no choice but to confront reality and let go.