The expression TO GET BACK TOGETHER means to start being a couple again after ending the relationship:
They broke up on Saturday and got back together on Monday.
They got divorced a couple years ago but are now thinking about getting back together.
Why didn’t you tell her that you and your ex-wife got back together?
Who would have believed that you and Jane would get back together?
I don’t think it’s possible we will ever get back together after what you said.
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