For Him
So, basically, this is my idea of the thoughts running through Elizabeth's head when she accepted James' proposal in COTBP.
No. No, no, no, no, no! She couldn't just let this happen. She couldn't just leave him behind to die! She loved him. More than she loved anything. Even herself. She'd have to save him, in the only way she knew how. She would accept the Commodore's proposal, and please her father. She'd do what was expected of her. She'd marry James, stay at home with their kids, sit by James' side when he took over her father's position as governor, she'd be seen and not heard. All things she knew she was expected of, but didn't want to do. But she would, if it meant Will would be found and brought home.
Of course she wanted to be with him, more than anything, but it's not like that would actually happen, he would never ask her, for one. He'd never feel the same way. And even if he did, her father wouldn't allow it. He was but a blacksmith's apprentice, she was royalty. Something she still couldn't understand yet had been painfully obvious for the past 6 years. When she and Will were young, they would play every day. Then, one day, it stopped. They were 14, and when she invited him over to play in the woods behind her mansion, he said no. And ever since that day, things weren't the same. But that absence did bring upon the greatest thing so far: She realized her love for him. She supposed it had been there all along, but his presence was so….assumed that she hadn't noticed. And then when he wasn't there…she just knew. Knew he was the one. And she'd do anything to ensure his safety. So, she accepted James' proposal, a proposal for a lifetime of misery. A lifetime without Will. She said yes. All for him.