Leia reflects during the night, and Han is by her side to keep her grounded. [ spoilers only if you haven't seen Return of the Jedi ]
Nights are the hardest time for her.
The war is over, but it's not over. It plays again and again inside Leia's head, taunting her with things she could have done differently, people she could have saved. Knowledge she gained during those last days appears to her, and she wishes she'd either never learned it at all, or learned it earlier so she could have used it to save people. Every night, Tarkin visits her in her nightmares, saying that she is the reason that Alderaan is being destroyed, that it is all her fault that millions of innocents will die. She knows he's lying, knows that he had known all along which planet would be destroyed, and even if she had given him the location of the Rebel Base, Alderaan would still have been blown apart. The Empire had to make an example of somewhere -- the fact that Alderaan was her homeworld was just a bonus.
Other knowledge, bittersweet knowledge, taunts her as well. She can spend hours sitting in a chair on the balcony of the apartment she shares with her husband, mulling over this knowledge instead of sleeping. She knows family isn't necessarily defined by blood, she knows this inherently, but still, the fact that she now knows the identity of her true father is sometimes enough to drive her mad. She doesn't grudge her brother for telling her this, nor does she grudge the way he told her. It was to follow the knowledge that she and he were twins, siblings, something she felt as if she'd known the first time she saw him, when he came bumbling into her cell on the Death Star, ready to save her. No, that was knowledge she was pleased to learn. She wishes, however, she'd never learned the other piece of knowledge Luke shared with her that night.
Darth Vader was their father.
He's dead now, his ashes scattered to the wind on Endor, but he haunts her still. His spirit visited her on Bakura, just after the Emperor's death, trying to make amends, but she wouldn't listen to him. She forced him to leave, to fade away and leave her alone to live her life, and now sometimes she wishes she hadn't. She doesn't hold her brother's view of things, that there was still good in their father. Vader had the blood of too many innocents on his hands -- including the blood of her adoptive family, and technically of Luke's as well. Vader overcame his evil long enough to save Luke, but to Leia, this doesn't make up for the hundreds of atrocities he committed across the galaxy.
She looks up at the sky, pulling her robe more tightly around her, her mind bustling with thoughts. She knows the moon is out there somewhere, even though she can't see it because of the millions of artificial lights on Coruscant. Even knowing the moon is out there doesn't comfort her. Again she hears Tarkin's voice in her head, condemning her homeworld and the millions that reside on it. Unbidden tears come to her eyes, and she places a hand to a suddenly tight and painful throat.
Then a pair of arms slips around her waist from behind, and she leans into her husband's warm and comforting weight. Han always seems to know when the nightmares are the worst, when she can't sleep, even when she's still in the bed beside him. He never complains, knowing she has more demons in her past then he'll ever truly know. He simply supports her, and she loves him all the more for it. Sometimes he tries to reassure her that nothing that happened was her fault, but more often he'll simply hold her, let her cry, offering silent comfort in place of flimsy words that often do nothing but make her feel worse, even when she knows that's not their intent.
She isn't sure how long he holds her, or if she even cries, but she feels his breath against her hair. "Come back to bed."
She doesn't resist him when he leads her to their room, helps her slip off her robe, and lifts her, settling her gently against the pillows as he pulls the blankets securely around her. He slides into bed next to her, again encircling her with his arms, and she breathes in his scent as her eyes slide closed.
Sometimes she doesn't know what she'd do without him. Sometimes he seems to be her sanity in an insane world.
Sometimes she wonders if he realizes just how much of a savior he's been to her.
She knows she'll never tell him that, but then again, she knows she doesn't need to.
He already knows.