Fear
Once he was afraid of losing her. Afraid that one day, he'd turn around and she'd be gone, bleeding, eyes wide and lifeless. Or scattered in bits across space. Or slowly slipping away from him on a hospital bed. Gone in an instant, like Daniel had lost Janet. That day, he'd held closely onto Sam when she came to see him, painfully aware, yet again, how anyone could be killed in a second, no matter how much she was loved. That fact sometimes chilled him, sometimes burnt him up inside. He was terrified of losing her.
And then he lost her. Not to a bullet, or a zat, or any one of the million ways there were to kill her. But to an ordinary policeman who stole her heart while Jack played by the rules.
And now his only fear is that he'll never be able to let her go, as he should.
Joy.
He'd actually forgotten what it was like to be happy. Not just merely not miserable, not just having her to himself for a few moments, but actually happy. Warm, relaxed, comfortable. Free.
It's been building for a few hours, the joy in his bones, his heart, his blood. From the second she stroked her cheek against his hand, through the moment she leaned against his office door and said 'I gave back the ring' to the moment she said 'lets go fishing'. And finally, he found perfect happiness when they arrived at the lake and she stood there, beside him, then turned, pulled him towards her, and kissed him.
And now; he's beside his lake, lazily and fruitlessly fishing. His closest friends are on their way, with beer. The woman he loves is sitting beside him, and she is finally his. He can touch her, smile at her, kiss her, tell her he loves her anytime he wants, and knows she'll respond in kind.
For a moment, he can't recognise the peaceful, warm feeling inside him. Then he realises.
It's joy.