we don't truly appreciate what we have until it's gone

— father regrets mistreating fl after realizing how similar she looks to her mother, ex-crush regrets neglecting fl once she stops giving him attention.

— ex-fiance only regrets outcasting fl once he finds her interesting.

— family regret abandoning fl when they need her for their own selfish gain.

— past ml regrets mistreating fl after she dies, family barely regrets mistreating and abusing fl when she stops putting up with their bs.

— ex-fiance regrets missing his wedding with fl, also regrets getting acquainted with the heroine, heroine regrets taking fl's past fiance and wants her new man instead.

— family only come to regret their neglect of fl when it's finally to late and she's done with their bs.

— step-father regrets using fl as a toy for entertainment when she goes missing and he realizes he loves her.

— family regret neglecting fl when they realize she acts exactly the same as her mother, prince ml also regrets not noticing fl before she completely dumps him.