He watches her grow old. He remains her best friend throughout her life. And he doesn't realize something important until it's too late.

They continue warding off the bad guys for most of her twenties, she gets stronger and stronger with each passing year. On her twenty fifth birthday, which he rented out a whole hall for, she laments the fact that she is one day going to look like his mother as she rubs at the nonexistent wrinkles on her forehead. He grins and takes her hands and kisses her forehead, insisting that even if she was as wrinkly as a prune, he'd still kiss her everyday. When she is twenty eight she tells him, drunkenly, that she couldn't bare to bring a child into their crazy world and he runs a hand through her curls and tells her that if she ever does have a child, he will die before they even smell supernatural danger. She rolls her eyes but thanks him all the same.

Her thirties are emotional and physical roller coaster rides, because she can't tax her body with magic as much as before. When she is thirty one, a dark warlock sends an arrow through her lower abdomen and the doctor tells her she can't have children. She insists she isn't sad at all, but they have a movie marathon with extra buttery popcorn and copious amounts of chocolate anyway. When she is thirty seven he finds her studying her body and coming to the conclusion that she will need to start working out. He thinks she looks perfect, though. But he joins her when she goes jogging and even when she meditates or does yoga because, what are best friends for, right?

In her forties, people start to give them strange looks when they are together, but he glares at them until they go away because she still looks like she could be thirty. It's not until she's forty three that she has a midlife crisis, if he didn't count the several ones she had in her twenties, and she spends days redecorating her house, only to return everything to the way it was a few weeks later. He still sees the springtime sun in her face, even though all she can see are wrinkles. At forty seven she jokes about passing soon and he doesn't laugh because he can't lose her that fast. Instead he makes a schedule of all the places she should go with him, and all the experiences she can have. She smiles at him, and it makes him feel equal parts warm and cold inside.

When she turns fifty, she retires from the supernatural gig, and he goes into retirement with her. They move to a small town on the other side of the country. Caroline visits every weekend, and Stefan, every fortnight. When she is fifty four, she complains that she can't move like she used to, and that she had pains in her back, her shoulder and her knees. He massages her joints and back, and she jokes about him being a good son, he smiles because he has more than a hundred and fifty years on her. He takes her dancing every Friday and carries her like a bride wherever she needs to go. Even though she gets flustered and embarrassed, he still thinks of her as the young petite girl he needs to protect. Menopause is not fun. She gets emotional and she's in pain and there isn't a damn thing in the world he can do to fix it, except be there. A year before she turns sixty her eyes take a turn for the worst and she can barely read without high powered glasses. She complains that glasses give her a headache so he reads her to sleep every night.

He argues that her sixties are her true prime because that decade is her most fun one. He takes her everywhere she wants to go. Australia, New Zealand, Egypt, India, Japan, even another trip through Europe. When she is sixty two he notices she has shrunk, because now she comes up to his chest. He is adamant that she not slouch when she is sixty five because he doesn't want her to get any shorter. She whacks him with a newspaper, and rolls her eyes. She still likes to eat pancakes with blueberries for breakfast and she admits that they sometimes let her forget how old she is and she can pretend things were like 1994. She wonders whether they would've aged if they hadn't found a way out from there. He tells her that she is still the most beautiful woman in the world, cute wrinkles and all. When she is sixty eight, for the first time she forgets where she is. She asks for her Grams and starts to panic, but he holds her until she remembers his name.

When she turns seventy two she insists on moving back to Mystic Falls. He takes her to the Salvatore house, because both her father's and her Grams houses were sold off. She often forgets who everyone is, and to her defence, Stefan and Caroline bring all sorts of people to stay for a while. Caroline's kids are grown and have their own kids. He is sure she can't tell who is who. She is just shy of passing seventy four when Alaric dies. She forgets who Alaric is on the day of his funeral, but she strokes his hand and holds him, patting his back, even though he wasn't that sad anyway. She forgets who Caroline is one day when she is seventy seven, when Caroline is helping her shower, Caroline tries to calm her but the only one she listens to is him. Her soft green eyes still sparkle when she sees him.

On her eightieth birthday she looks into a mirror and can't recognise herself. She spends hours, catatonic in front of it but eventually she turns to him and asks him to read to her. He tells her stories of a beautiful young girl who sacrificed too much for the people she loved. She caresses his face and tells him she isn't that senile. When she is eighty four she has a stroke. He runs to the hospital and is more panicked than he feels he has ever been. He has to compel them to let him stay with her, in her own private room and he is told that these are her last days. He lies down beside her tiny frame and holds her. She smiles weakly at him, heart monitor beeping away in the background, as he talks and talks and talks. He only talks so much because it's hard for her now. She only has to look at him with those beautiful green eyes for him to know what she wants to say. Everyone visits her, one by one. Most of her human friends are dead but Donovan isn't, so his grandson wheels him in, and Matt talks to her about their life before the supernatural. Jeremy makes the trip to see her, even though he's just as old. Caroline comes with Stefan and makes him leave her side. He hears Caroline apologise and then talk for hours about nothing but he hears a weak laugh so he thinks it's worth it. Stefan says his farewell too, and he can sense her getting weaker. He is the only one to stay as the night closes in because Caroline was crying too much to stay. It is nearing 3am when she wakes him up, by poking his chest.

"I had a nice life. Thank you, Damon." He tries to smile but it turns into a frown because she isn't dying yet. They don't end up being her last words. No, the last thing she says to him is something to do with knitting needles because she had made him his very own ugly Christmas sweater. Except that it wasn't ugly, it was beautiful and it was black with a small bonnie embroidered in green and a larger Damon embroidered in red. He is wearing it, despite the May weather when she closes her eyes. There is a small smile playing on her lips and Damon could fool himself into thinking she just fell asleep listening to his voice.

He doesn't think he has cried as much as he cried on that day and he doesn't think he will ever cry as much as he did. It's pointless because she told him she enjoyed her life, told him that he was a better best friend than she could have hoped for. He doesn't understand the tears and he doesn't understand how hollowed out he feels when he turns and she is not beside him.

Elena comes to the funeral. But he can't bring himself to look at her because he is staring at Bonnie's coffin. Caroline can't seem to stop crying and she can't look at Elena either. The funeral is long and slow and Damon can barely steel himself enough for the speech. He talks about her life and the unsung hero she truly was, he talks about the fact that he was glad that after everything she went through, the only thing she succumbed to was old age. Caroline can barely contain herself so she holds Stefan's gaze throughout her whole speech. He doesn't really hear what she's saying, doesn't want to because he is on the brink of tears again.

Elena finds them, eyes swollen, afterwards. It's not Elena's fault, he knows this. And he recalls his own words as they haunt him. When he looks at Elena, all he sees is not-Bonnie.

He keeps pictures of her in his wallet. One from each decade, of them together. It is the strangest feeling, because he had never noticed the passing of age with anyone else. He wishes, suddenly that he had taken the cure, because life without Bonnie doesn't seem fun, doesn't seem warm. There is one picture of her by herself, and it is one where she is smiling widely and happily.

He is sitting with Elena, Stefan and Caroline in front of the fireplace drinking his fill of bourbon - which he'd sworn off once the doctor told Bonnie to stop drinking - when he realises. He may just have been in love with her.

When Elena's lips ghost over his, it doesn't feel right because the only thing he has kissed for a long time is warm earthy brown forehead wrinkles and hand veins. When Elena confesses to wanting to spend her whole human life with him he thinks it's absurd. As if he hadn't just spent sixty years loving something else.

He spends more time at her tombstone than he likes to admit. Mostly because he really misses the sound of her voice, and she would probably tease him for it. He talks to thee stone for hours, and he laughs at himself because he used to think it was stupid. He leaves a different flower every day.

He and Elena fight a lot. And have a lot of sex. He takes the cure because he doesn't think he wants to live for that much longer than Bonnie, anyway.

He still visits her grave every day. Even when his joints are rickety and creaking. People often think he is visiting his dead wife by the way he talks to her. But Elena's grave is in the next section. Their marriage turned cold after their thirties. They had a child, and she was a teacher at a school in Mystic Falls. He was sure that Bonnie Gilbert-Salvatore knew more about Bonnie Bennett than her own mother because she's all he ever talked about.

He passes almost two decades before her, at the ripe age of sixty-five. Liver failure, she had always predicted it. He wants to be buried beside her, laughable because this is her family grave.

When he wakes up he is young again, and a twenty something year old Bonnie Bennett gazes at him with sparkling green eyes.

"I named my daughter after you." He says.

She presses a soft kiss to his hand. "I know."

"You don't know how much I've missed you."

"No, I know. I watched you grow into an old man, too. I have to say, I think I aged much better than you."

"Ah yes, well that's because you had me taking care of your every whim."

She presses a chaste kiss to his mouth. "I know."