I'm always a little bit stunned to hear someone trash a relationship or person that they once cared for. Like a husband suddenly telling his wife that he doesn't love her or a friend telling another friend that they can't stand them.
I understand that people get hurt. I get that concept very easily. Who among us hasn't been hurt in our lives? But the way we end relationships has to be respectful or we take all that hurt and anger with us to the next relationship. That's true in any type of relationship, including friendship.
You might think that you're "over it" and therefore you want to tell an ex-friend off so they know they hurt you. Well chances are, they probably know it. Maybe they are in a bad place themselves so they can't be a friend right now. Maybe they just don't care about anyone but themselves.
Regardless of the reason, your behavior is the only important thing, because it will dictate how easily to move on from the friendship and how your current friends think of you. Here are some ways to end a friendship in a respectful way, with some more info on why this is so important to do.