1
general::
Reject, abandon, as in They'd lived together for a year when she suddenly threw him over and moved out. This idiom, possibly alluding to throwing something or someone overboard, was first recorded in 1835.
American Heritage Idioms
2
general::
Phrase(s): throw someone over
to end a romance with someone. • Jane threw Bill over. I think she met someone she likes better. • Bill was about ready to throw her over, so it’s just as well., Phrase(s): throw someone or something over someone or something
to toss someone or something over someone or something; to lay someone or something across someone or something. • The wrestler picked his opponent up and threw him over the referee. • He threw his opponent over the ropes.
McGrawhill's American Idioms And Phrasal Verbs