Soundtrack: Mirrors by Justin Timberlake

Just a little idea I had, hope you guys like it.

...

When Barry Allen went into the Speed Force, he didn't just see his timeline. He saw all of his timelines, he saw the multiverse. Every way his life could've gone, slamming into him at once. All the possibilities flashing before his eyes, and he saw it all. Somehow, it's not surprising that in most of them he's the Flash or some variation.

What is surprising is how many universe's he's not with Iris West. Barry had always thought they were destined to be together, that the very cosmos dictated their entwined paths. But in truth, there are only a few universe's where Iris and Barry are in love.

However, there is one constant in the never-ending flow of worlds. Wherever Barry Allen is, Caitlin Snow is always there. Like two planets forever locked in a gravitational pull, they're always together, orbiting around each other. Maybe not together together, but somehow they always find each other, no matter how different the circumstances. In so many worlds they are friends, the best of friends. Just like Barry's home world.

In another life, they are enemies. Well, enemies is too strong a word.

Rivals.

He is the Flash and she is Killer Frost. They were never friends like they were where Barry is from, yet somehow they never fail to be there for each other. They fight and they make a show of it, but at the end of the day, they will always have each other's back. It's a strange understanding between them. And they do, until the very end.

In one reality, they are villains together. They aren't quite evil, but they aren't exactly good either. Yet they are unflinchingly loyal to one and other, and they make one hell of a team. They are lethal in battle, but somehow when they are alone together they melt. Their cold, hard exteriors peel away to reveal something softer, more familiar. Eventfully the duo meet a bloody end, but like everything in life, they do it together.

In yet another world, Barry Allen and Caitlin Snow have no powers at all, they both work at Star Labs. They have a wonderful friendship and a life full of could-have-beens. They end up married to different people, yet someone remain life long friends.

Finally, Barry stumbles into a universe where the Flash and the Frost (and the Vibe) are all superheroes together. Barry and Caitlin fight side by side, protecting Central City. A smile tugs at Barry's lips, a part of him secretly hoped his world could be like this one day.

In one universe, Barry and Caitlin meet at Jitters and end up married with 3 kids. They're scientists and they open their own lab, doing a lot of good in their lifetime. They grow old together, surrounded by grandchildren. Barry thinks maybe he should be embarrassed, because his Caitlin is just a friend, and nothing more. But all he can bring himself to feel is a warm sensation in his chest, and a persistent longing.

There's a universe where she dies and he goes down an unspeakably dark path. He loses her and he burns the world down. She loses him in another life, and she freezes it.

There's even one where they end up together after that night full of drinking and karaoke. There are endless possibilities, endless lives. So many different careers, so many different paths they take. Yet they always end up squarely back where they belong. Together.

Then there's one where they have it all, it's a shadow of what his life could be, really. They are best friends and partners. They are heroes and scientists. They have wonderful family and friends. They do amazing things in their life and live it to the fullest. They are so very happy, and by the end, they have done truly amazing things. Barry and Caitlin Allen go down in history.

A thousand probabilities all bombard Barry's brain cells, and a thousand moments flashing before his eyes. Smiles and tears, sickness and in health. Tragedy and happiness. Hundreds, no thousands, of moments all falling into an epic story, regardless of where it takes place. A beautiful mural painted across the multiverse, etched into reality itself. As their lives play out before his eyes, he begins to realize maybe they are ones who are truly written in the stars.

Then finally Barry arrives on a certain universe. It's dark and sad and empty. It is a world where Barry Allen never knew Caitlin Snow, ever. A world that seems so meaningless and gray. Barry thinks it must be at the end of the cosmos, the very end of the multiverse before it drops off into oblivion. Because that's what it feels like, so very empty and cold. It's a world without the sun, a world without color. Barry Allen lives his life in a boring nine-to-five job, with nothing interesting (or good really) ever happening to him. Meta-humans don't even exist. There's a gaping hole, an endless void.

Just when Barry thinks he can't take it any longer, there is a tug, as if some unknown force is pulling him somewhere. Then suddenly he feels himself being yanked back, back through time, back through the universes. He picks up more and more speed until the worlds are nothing but a blur.

Then all at once, it stops. Barry hits the hard pavement and suddenly he's staring up at the brilliant blue sky. There's a moment of clarity, where he's fully aware of everything.

By some miracle, he's out of the Speed Force, he's back home. He is both happy and sad about it. He is happy to be home, but after watching his alternate versions for so long, he realized that he and Caitlin have been living in one of those worlds where they aren't together. They are existing entirely in the realm of 'what if.'

The memories begin to rush back, threatening to overtake Barry. Memories of his timeline, the multiverse, all happening at once.

While he still has a bit of coherency, Barry makes a promise to himself. He is going to make sure that this isn't one of those 'what if' universes, he isn't going to let Caitlin slip away. Something within had been awakened, something he had buried under meaningless excuses. Something that had always been there but he had been too blind to see.

Barry Allen loves Caitlin Snow. And judging by what he now knows, it's not that far fetched.

He doesn't care how long it takes, he's not going to waste his chance. Because he realizes it could be so much worse, he could have not known her at all. He realizes he could have so many wonderful things if he could just wake up and stop living a lie.

And he's going to, he'll make sure of it.

An instant later, the memories wash over Barry like a flood. and his mind becomes lost beneath the waves.

After that, everything is a blur.