[CAxrrAYN]

Personally, if someone approached my father (if he approached my brother, I would without doubt say no) with regards to my marriage, I would only consider it if I knew the person before hand and they were asking my father out of respect.

In your situation, she knows you (i'm assuming, since you're family friends). So if she's said no three times, its a no. If you think you're still the perfect person for her than show her through actions that you're compatible. What about you do you think that she dislikes (is it something that can be changed ex. habits? or something that is more embedded in you ex. your personality)?