You were part of Dom Toretto's crew. You raced, hijacked trucks, and all that lovely stuff. You were one of the best drivers they had seen, that's why they liked you.
When Brian joined the group, you could tell he was different. That's why you liked him. You liked him so much that the both of you started dating.
You had an amazing relationship. It was healthy, happy, and full of love. But Brian picked up some of Dom's habits.
Like Dom, Brian didn't play about his car or his girl. That's half the reason him and Dom would get into scuff ups.
But after you had won a race, some guy had come up and started flirting with you. You asked him to go away and even tried to get away yourself, but with the hoard of people around your car, you couldn't really escape.
Letty was the first who noticed. She pointed it out to Brian and Dom. Brian lost his shit, pushed through everyone, and slammed the guys head into a wall.