Help!!! My boyfriend wants a breakup with me

Welcome to Dafy's World

A female friend where I do some daily work called my attention to discuss with me a pressing issue. Surprisingly, it was a relationship matter.. And she asked for help on the right step to go about it.
According to the damsel, her boyfriend who she had been dating for over 4-years suddenly grew a strange attitude, acting weird. It all started from a goodmorning call and all of a sudden he begins to insult her, vomiting negative words (She didn't mention). "He had refused to apologise despite his wrongs," she said.

"I'm currently expecting my boyfriend to wake up one morning and call for a separation because he’s always wanting to take such step." She added.

The young girl, whose name is not encouraged to be announced here added that they've not been communicating for the past one month and when she tries to reach him, her calls gets ignored.

What do you have me do?! She seek for advice.