The FL is rich when she's younger and treats the ML who likes her like shit. Years later, it's reversed. The ML is rich and the FL is poor. She reunites with him and tries to befriend him, but he acts cold and hateful despite secretly loving her. They get together. The SML also courts her and she likes him before she falls for the ML.

Has some of what you are looking for, but with great exceptions:

  • Pheonix - they loved each other  but was separated
  • Wonderful Days - rich FL was so smitten with poor ML
  • My Sunshine - FL chases after the ML in their college days 

Cunning single lady. Its very similar to what you're looking for but the female lead wasn't poor to rich, they were both poor so she hated him for being poor and left the ML  but later on ML became rich. Its a really good one I reccomend you to try watching. 

Ms Hammurabi

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