Mr.Swift's Sweet Addiction

"I like you, love you and crave for you. And when I don't get as much as I want, I'd quit life the very moment"
"This is not love"
"I know this is not love. This is addiction"

Rose Evans the daughter of a middle school teacher met Aydrien Swift the son of a politically active businessman when she was newbie in her college. They were nineteen and at that time and they loved each other like there is no tomorrow. But something terrible happened and their relationship came to an end.

After four years they crossed paths but on a different note. Now she was a caregiver and he was her patient. She hated him and blamed him for all the nights she cried, the people she lost and her current situation.

What happened before four years that she hated him so much?