Is Jason struggling hard trying to deal with envy that Tim has taken his family, his place in the court, his dragon? Of course, but at the end of the day Tim never owed Jason’s memory any respect or loyalty. But the egg he stayed up late whispering his hopes and notions of friendship and happiness and protection, patient and gentle for years, despite everyone telling him it was a lost cause. His egg –now a dragon– has forsaken the only person to dedicate themself wholeheartedly to its safekeeping. So Jason might eventually get to a point of understanding and tolerance with Tim but the little dragon must have felt him off in the distance and given up on him. It is the only way the pieces fit together. How can Jason accept that? He never faltered in his belief in his egg but as soon as he seemed weak it discarded him for someone easier to love.
It certainly seems that way to Jason, yeah :/
(Jason has no way of knowing that Robin hatched only a few weeks after his perceived death, and that the little dragon was inconsolable for many months to the point of near starvation, and that Dick and Bruce were so wrung out about Robin’s impending loss that Tim snuck into the dragon caves to try and coax the baby dragon to eat something, and that Robin didn’t just latch onto the first best person he saw, no, Robin felt that Tim came the closest to Jason’s kindness and uplifting spirits for the first time in months….)