THIS ENTRY MAY CONTAIN SPOILERS AND WAS WRITTEN DEPENDING ON CHOICES MADE IN THE GAME
Jackie helped V during previous tasks, such as getting goods across the NorCal-SoCal Border. When he was asked for help again, Jackie immediately sprang to action. Even though things went sideways for V, Jackie was there to help him out and start over. They were choombas through thick and thin.
When their first big gig arrived, they were both on edge and roaring to go. But things went sideways for both of them, despite careful planning. They managed to make it out alive by sticking together (with some help and luck) when the time became dire, though Jackie sustained injuries.
After Jackie succumbed to his injury, V sent his remains to his family so they could have a proper farewell. It also allowed V to help restore the rocky relationship between Misty, his girlfriend, and Guadalupe, his mother. The two would eventually become friends and even have a family dinner together. His death showed V trying to get into the “major leagues” had a price, but it also gave V the motivation to move on and continue in the name of their friendship.
That is why, in my eyes, Jackie is and will always be remembered as V’s best friend.