That being said, I think your best approach should be this: Write her a letter and tell her the same things you told us, about why you admire her for the sake of Allah, how she inspires you to be a better person and Muslim, and how you believe both of you as a team can make a good marriage between the two of you for the sake of Allah. Also, please tell her to tell you in response if she absolutely feels that therein lies no possibility in her heart for your proposal being accepted, confessing to her that you wanted to make a final try to see if she might change her mind and tell her you will respect her wishes regardless of what she decides but urge her to take some time to think rather than give you a response immediately. Also, urge her to pray Istikhara if she hasn't already done so. Please have the letter be read by her Wali to see that the content is judged appropriate and halal before having the Wali give the letter to her.