The two had a falling out which ended their friendship.

After a heated argument, the two end their friendship.

"You forget, though, that we ended our friendship only because it seemed advisable."

It is implied that they have words and decide to end their friendship.

Even now I was not sure why he had erupted, one day, into the violence that ended our friendship.

Hank then feels bad about ending his friendship with Bill.

He leaves soon after when Peter ends their friendship.

She apologizes and they are able to end their friendship on good terms.

A few years later, he ended his friendship with Fratianno.

This strained and most certainly ended the girls' friendship.