The phrasal verb TO BREAK UP means to end a romantic relationship, marriage, etc.:
After dating for so long they unexpectedly broke up last week.
This marriage is going to break up if you don’t try a bit harder.
He broke up with his girlfriend when she told him she loved someone else.
This marriage was a misunderstanding, but it’s not me who wants to break up.
What do you mean? Are you breaking up with me?
Here’s the video version of the article: