A lot has changed in the past 6 months of my life and decided that now is the perfect time to get rid of anyone who doesn't bring value to my life

This person in particular, is someone i used to hang around with a lot in my past life, but he hasn't changed since high school. Basically the definition of toxic, this guy does nothing but smoke weed and drink every day, uses and manipulates people to get what he wants and is so stuck in his ways that he will never change. He only ever gets in touch when he needs something

Decided to go no contact for several months as people like that have no place in my life anymore. But unfortunately, he is not giving easily and trying to contact me through other peoples facebook and ringing my phone from different phone numbers in a desperate attempt to get back into my life

What do i do? I feel i should just carry on ghosting and let him work things out for himself, but he doesn't appear to have much of an ability to self reflect, and struggles to realise that i'm no longer who i was and the disrespect he has shown to me in the past has no place in my life anymore.

I am very hesitant to even waste my time sending a reply as guaranteed he will start acting bitchy and make out i'm the asshole, when to be honest, I've just changed.

Why do i feel slightly guilty about all of this? i know its for the best and i have a whole new circle and lifestyle now and have no desire to go back to the past, what is done, is done. I've already moved on, but it seems like some people just can't accept change and expect things to stay the same forever

What is your experience with ghosting people from the past?