1. ML doesn't love FL and loves someone else ..... FL loves ML but her feelings are unrequited ... so somehow she changes her personality ( for example She decided to forget about her feelings and be tough or something)... But then ML falls in love with her? He is trying to get her back. And I want it to end after all that they will be together!
(She doesn't have to change. I mean, after he hurt her feelings, he somehow hmm noticed that she was distancing herself from him ... that she was so different ... that she gave up on him ... and he falls in love with her. He cares for her more than before. I prefer he were such a cold man. And it doesn't have to be second girl either, he just rejected FL then oh well he fell in love.)
2.. I want something to happen to FL and ML to worry ... she passed out for some unknown reason (only she really knew why, for example she is sick or it has to do with something supernatural ...) or protected him.