Yvonne Whital

They were engaged 5 years ago, but the heroine dumped him days before the wedding via a letter.  She left him because her grandmother who raised her had cancer and needed her care.  The hero had been offered a very important medical internship out of the country: if she had told the hero she needed to stay at home with her grandmother, the hero would have stayed with her and given up the internship, and she wanted him to have the career he wanted.  She was trying to be selfless, but her abandoning him made the hero very bitter, he never married after his relationship with her.