for this type of people, they only wanted to do things to get
response from you.
They will try to be nice, pityful and if all does not work - they
will try nasty - even if he can get a response of you sms him to
tell him off or a call to scold him.
Don't fall in the trap, if you response, to him he will take it
that he still have a chance.
Be cool, just ignore him.
If you want can change phone number. If you decide to keep the
phone number, then when he sms, just delete it, never reply. If he
call just hang up.
Remember he is nothing, if nothing call or sms - what is there to
react to, and response to ? don't even try to waste time of thing
of nothing.
Statement like we still be friends will just give them hope, forget
it have a total new clean break.
Go to the police or the court to get a personal protection order
which will force him to keep a distance from you only when there is
a danger or he pester you in person.
But if he just sms & call you, well just ignore him,
threatening to call the police to him is still a welcome
response.