I would say it sounds like your brain trying to show you all the things you missed whilst with her, the emotions and such.
you clearly still love this lady even if she is unable to show emotions.
it could be she has been through a rough past which has left her unable to show her feelings, she could be scared of being hurt emotionally if she shows she has any. it is totally your choice if you wish to try again to win her affection or not, but be careful, girls like this need very gentle and consistant reminders that you will not hurt/let them down, but given time and consistency and understanding her emotions may flood back and need help to be sorted out into good and distructive ones.