Well if you didn't actually tell him during your phone call on friday that it was over then he's going to keep hounding you until he hears it from you, so you should probably do that. Otherwise he'll be convinced you are just having a sulk and trying to teach him a lesson until he's heard the words 'it's over'. So send him one last, very clear message, via whichever means is safest then block him on every single thing and make sure all your settings are on private for FB etc.
Don't get into a long drawn out debate over it, DO NOT agree to speak to him in person or on the phone, do not apologise. Just:
I've realised I am finally done with this. We clearly want very different things from life, so you are now free to behave exactly as you like without having to answer to me. There is absolutely nothing to be discussed or worked out between us and I will not change my mind. Now you've heard me say it, please respect it and leave me alone. If you turn up at my house or work, follow me in my car or harrass me in any way I will go to the police and take out a restraining order.'
Then block him immediately and do not give him a chance to open up a conversation or to cry or beg.
If you have any stuff of his at yours, leave it on his doorstep when he's at work. If he has any stuff of yours, consider it a small price to pay to lose it, if it means you never need to set foot in his house or speak to him again.