Disclaimer: I don't own Doctor Who, but if I did, this is what would happen…

AN: So, I'm back! Hopefully I'll see this one through. I really, really will try. I have it all planned for once, and a lot written out already, so it's looking hopeful!

Chapter One: Prologue and Epilogue

I'm in my tree again, climbing up through the rough branches and cool leaves until I come to the seat. It's not a real one, of course. Just a natural alcove in the tree that just about fits me perfectly. From here, I can see everything and nothing. Sure, the leaves hide the ground, and I can't see much of the horizon – but upwards it's a different story. I don't know why, but the sky just feels so much closer here – as if I could just step out onto a passing shooting star and leave the world behind. The endless canopy is a perfect, picture book blue today – not a cloud in sight. I settle into the seat, letting leaves caress my body as I stare up and dream of the stars.

Suddenly – I've almost dozed off – there's the slightest of rustles next to me. I crick my neck, I turn so fast. He's here again. I keep quiet though, trying not to let on I know, until his face peers out from between two branches.

"Hello," he grins,and I wriggle over to make space on my seat. It's a squeeze, and I always end up half on his lap, but to be brutally honest I don't exactly mind.

"Have you been here long?"

"A while – you're late again."

"Oi!" I'm indignant. "You never exactly tell me a time. 'Oh, I'll be around sometime after lunch next Tuesday'...'I might pop in after midnight on the third of June'... How am I supposed to guess when you'll turn up? Telepathy?"
"You could always try," he retorts. "Or just move into the tree 24/7."

"Why do we have to always meet up here anyway?" I ask, knowing the answer already. It never changes.

"Because at some point soon I am going to become a little girl's imaginary friend in the tree, half a lifetime ago."

"But what does that even mean?" I sulk, frustrated.

"It means..." He taps me on the nose. "That time travel is complicated."

I relent then, accepting this – as I always do, of course – as true, and more importantly not wanting to turn this into an argument. The last time that happened, I nearly broke my neck in my haste to get out of tree. He never leaves before me, of course, and I never see him arrive; when I was younger I actually thought he lived up here in the trees. Only coming out every now and then to say hello.

The talk turns to other, topics – school, friends, Mum and Dad and Bennie. It never used to occur to me to ask him about his life, and now I think it would be too awkward. It's so easy talking to him though – I just pour everything out and he listens, understands. Eventually, though, he asks me the one question I had been praying to avoid, even though he'd been asking it every visit, now.
"And...boyfriends?"
"Well," I begin, looking down and buying a few seconds time. "There is someone I like, I guess, but I don't really know how to start anything."

"Just ask him out?"

I almost laugh. If only it were so simple.

"That's not exactly possible."
"Ah. Your parents would find him wildly unsuitable."
"That's an understatement." And that's not exactly a lie, I tell myself. Of course they would.

"Bummer," he sighs, slightly awkwardly, and I have to smile. He doesn't make this any easier, obviously, but it could be so much worse. "So...want me to check your French vocab again?"
Though I groan theatrically, my standard response when he switches to Teacher mode, I'm grateful for the change of subject.

It's late, way too late, when I next stand up to peer through a gap in the leaves to check the church spire.

"Shit!" I gasp, and hurriedly repack my rucksack with books, uneaten apples, pens.

"River..."
"What?"
"Come on now. You can't swear in front of your imaginary friend and not expect a bollocking."

I'm about to snap when I get it, and catch his smirk.

"Very clever, mister. But I'm late, Mum'll be furious."
"I know, I know – sorry!"
"Nah, don't apologise, not your fault."

I struggle onto a lower branch, and stand up again to bring myself up to his eye level.

"Well – bye then."
"Until next time." He pauses, seemingly searching for words. "River...when did you last see me?"
"Two weeks ago exactly," I answer promptly. "After school. When did you last see me?"
His eyes grow distant, as they always do when he's thinking about Future Me.

"Just before I came here. You're thirty-three."
"Shut up!"
"What?"
"Shut up! I'm never gonna be that old."
"Oh, you just wait. I rather think you'll enjoy it." He gives me one, searching look, and stoops slightly to kiss me on the cheek. I've hardly had time to recover when he deals his blow. "I'll be back on Boxing Day at about ten in the morning, OK?"
"Boxing Day! That's -" I count quickly - "Four months!"

"I know...Nothing I can do, it's already been and gone for me."
"Yeah. Well," I mutter, furious. Months! "See you."
And I climb out of the tree, not bothering to turn around for a final wave. Four months!

-x-

The Doctor watched her go, smiling slightly. She would have forgiven him by Christmas – in fact she would be so happy to see him he would almost fall out of the tree.

As he lowered himself out of the tree and walked back to where he'd left the TARDIS two miles away, the Doctor allowed himself the time to think, as he so often did, about the big fucking mess he was in. He didn't know what was worse; the raw, aching gap where she should be, the ever-present and increasingly redundant adulterer's guilt, having to sit in a tree and be an imaginary friend to a little girl, or share a life with the woman she grew up to be.

What the Doctor did know, however, was how River would react to him coming back now, with her locked in the TARDIS Library; it was the first time he'd had to leave her behind. According to River, he did it all the time, and she'd grow used to it soon enough – the Doctor just wished there was a way for her to tell River that.

Yeah, time travel could be a bit of a bitch.

AN: Hmmm, too Time Traveller's Wife? Please review, I honestly would like some constructive feedback. Also will definitely reply to all signed reviews and also make an effort to read and comment on some of your work in return! xx