Looks good! One small thing - I don't think people ever tell others to 'be fine'. 'Be good' is frequently used and that means something like 'behave well, be a good boy / girl' (but mostly used for adults). Would that convey the meaning? Or is it more something we could write like a wish? (eg 'I hope you'll be ok', 'I hope things will work out for you', 'I wish you well')
Thanks! No, it is not "be good" here, then. Because it doesn't mean "behave well". It's like a wish as you say, the writer wants her to be fine, to feel good and take care of herself. Probably, it also means in a secret way "Stop being sorry about our split." You know, when the lovers split up, there is always a conversation like this