How to get your ex to changer their feelings about you?

i have been with this girl for a fair amount of time she recently broke up with due to the fact she said her feelings had changed for me and wanted to be friends i just love this girl so much i need to have her back and i dont know what to do she also said i deserve better than her i told her i dont want better i want you HELP PLEASE!! A MANS HEART IS IN NEED