Harassed by the father of my ex

I have an ex and recently his father reached out to one of my friends, actually my best friend and started texting them about how I was a bad influence and had bad parents and that I will make bad decisions in the future, he also said I had my own person problems and the father told my exes best friend (in person) that I was a whore...I’m 14 and the father is in his very late 40’s or early 50,s....I’m not sure what to think of this..any comments about what I should do or any thoughts about the situation I would welcome