This story contains SPOILERS FOR EPISODE VII- THE FORCE AWAKENS
Leia had not wanted to have children.
Once she had learned of her heritage, she became terrified that her children might follow in Anakin Skywalker's footsteps. Even after all these years, she could not think of the man that was Darth Vader as her 'father'.
Han had quite honestly not cared whether they had children or not. But as a Princess of Alderaan she had been raised to do her duty. That included carrying on the Organa line, even if she had been adopted into it. There was no longer any throne for her offspring to inherit, but her children would likely inherit another kind of power. If the Jedi Order was going to be rebuilt then those strong in the Force need to breed, to put it bluntly.
So Leia did and gave birth to a son. She named him Ben, after a man she never met, but had changed the lives of both Luke and Han. She knew Obi-Wan Kenobi had once been a good friend of Bail's and had apparently helped her mother escape to give birth to Leia and Luke.
But she had really wanted to name her son Bail, after her real father, the man who had loved her and raised her. Not after the man who had failed to prevent Anakin Skywalker from turning to the dark side.
Leia had loved her son. She had loved the way Han had softened around the boy in a way she had never seen from him before. Han, for all his ingrained pessimism, had never been cynical about their son's future. She had loved the man all the more for that. And they had been happy.
But there were so many times over the years that she wished her son had not been born strong in the Force. It was a terrible burden. It was even more of a burden to be the grandson of Darth Vader. None of them, not Leia, Han, or Luke, could shield him from that no matter how hard they tried.
Now Leia wished so many things. She wished she had been stronger against the pressures of duty and decided not to have a child. She wished that she had named him Bail. She wished she hadn't allowed Luke to take him away to train at his new Jedi Academy when the boy was still so young.
She wished there was anything she could have done differently, so she would not be here sobbing in Chewbacca's arms, both of their hearts utterly broken.
Because Han was dead and her son had killed him.
