McDreamy catches Mere leaving the hospital as another pretty Christmas song starts up. He asks her if she's okay, and she returns the sentiment he had at the beginning of the episode: "You know, just the holidays." McDreamy says he does know, and they wish each other a Merry Christmas.
Cut to McDreamy walking into Joe's bar. He gets a drink, which awesome Joe has already poured for him (single-malt Scotch, for those of you playing at home), and goes to sit next to a radiant-looking Addison. Too bad she's about to get her heart broken. She asks after Tim, and McDreamy says he woke up smiling. Oh, good, they can get back to the crazy posthaste. Addison says she's drinking hot buttered rum, because of Christmas, which they both used to love, hint hint. McDreamy finally drops the bomb we all knew was coming: "Christmas makes you want to be with people you love. I'm not saying this to hurt you, or because I want to leave you, because I don't. Meredith wasn't a fling. She wasn't revenge. I fell in love with her. That doesn't go away because I decided to stay with you." He takes a big sip of his drink, and Addison, poor Addison, who I love to hate and hate to love, tries to take it all in. We pull back to an outside view of the doomed couple, and Mere voice-overs, "There's an old proverb that says you can't choose your family. You take what the fates hand you."
Cristina comes home to Burke's, exhausted from living with her newly-huge heart, and sees that Burke has placed a menorah in the window. She smiles, immediately undresses, and jumps into bed with him. MereVO: "And like them or not, love them or not, understand them or not..." Cristina tells Burke that Justin took a turn: his fever's down and his BP's up. She snuggles against him as Burke says, "I wonder what got through to him." Aw. MereVO: "...You cope."
Fade to Mere's. Izzie is lying under the Christmas tree, looking up at the lights like she's eight years old. Mere walks in and joins her. George follows, and then their new dog. It is, I have to admit, adorable, and Izzie looks absolutely GORGEOUS here under the tiny lights. MereVO: "Then there's the school of thought that says the family you're born into is simply a starting point. They feed you, and clothe you, and take care of you, until you're ready to go out into the world...and find your tribe." We pan up the Christmas tree so we see only four sets of legs sticking out, and the doggie gives a happy bark. Merry Christmas, everyone, and I'll see you next year!