From the original lover dance partner to be made into ordinary friends, meaning: not continue to be lovers, to be ordinary friends in the relationship together.
Your sentence reminds me of a neighbor aunt:
My mother's neighbor aunt, she is a very cheerful personality, the biggest hobby is square dancing. Every time after dinner, will go to the square downstairs to dance to exercise. Later on, after a long time to know a man, probably and auntie's age is about the same, and auntie it is single, so she did not think of other places. The two became lovers in a natural way.
One day, Auntie found my mom chatting about the pain in her heart. It turns out that the man has a family, the beginning of the aunt did not know, and now want to separate, the man is not willing. With the change of time, Auntie almost do not go to the square dance, and the man will occasionally come to her, but according to my mom, they have become ordinary friends.
So a lover relationship is a dangerous relationship and should not be continued, no matter from which side of the acquaintance. The best thing to do is to socialize together as normal friends so that you can avoid unnecessary trouble and embarrassment.