Two days ago, something happened. We reached the nine month mark of this twelve month-long trip, and it felt great.

Admittedly, nine months is not quite the 22-month gestation period of an elephant, but the thought that it's long enough to grow an entire human being is somewhat alarming.

Although I feel wonderful and springy and bouncy currently, I haven't always ... and when things on the road get bad, after this long away, they're REALLY bad.

As I say, right now, everything is peachy. We're in love with Ubud, we're about to go and stay with lovely friends in Hong Kong, and then to meet up with another great friend whom we'll travel to China with.

But when you're tired and sick, and you've been away for this length of time, you begin to question your sanity.

Thus far, the trip has delivered: Giardia (once for Andrew; thrice for me); food poisoning with high fever (Andrew); unidentified virus with fever (both of us); upper respiratory tract infection with fever (Andrew); tonsillitus (both); food poisioning straight-up (me); and a chest infection (me).

Nothing makes you want to bawl like a baby and run screaming from the developing world faster than feeling like death warmed up, particularly when it drags on and on ...

But the upside is periods like right here, right now. When you feel great, you REALLY feel great. It's all very Julie Andrews, 'raindrops on roses and whiskers on kittens!', sickeningly over-the-top, happy sort of stuff.

What's probably harder is the bone-crunching tiredness that comes with moving around every two days over a period of nine months. It truly is the most unbelievably debilitating feeling, and it has shocked me.

I know that my friends who have babies will be reading this scoffing, and rightfully so. I'm sure that you could tell us both a thing or two about tiredness.

But even so, I have to mention the Mack-truck-like force of the exhaustion that comes upon me from time to time.

It sneaks up at first - building, building - and then, BAM!

You're on the verge of bawling like a bub because you can't face the thought of packing up even one more time. Moving hostels seems like moving the earth itself. And as for catching overcrowded public transport with an 18 kilogram backpack? Pass the Valium, and quickly.

The worst strectches of it (which last days or weeks at a time) are reminiscent of the feeling you get from pulling an all-nighter to get something important done. The resulting tiredness leaves you zombie-like and disassociated from your body.

Things come into your head like, 'Gee, I should really move my arm now,' and all that happens is you stare at said limb and wonder why it's not moving.

Scary stuff.

Still, nine months on and we're still having a ball. The tiredness always wanes in the end, and there's another something amazing to see. The pay-off is BIG.

Sometimes, it's like there's almost a frustration at the size of the world. The idea that you could travel for nine months and have yet to even scratch the surface of the world's charms is staggering. No matter how much you travel, and how much you see, there's always more out there.

In the traveller mentality - where so much depends on demonstrating your own 'worthiness' by showing how much you've seen and done, and how super-fabulously au fait with everything you are - there's a strong temptation to get depressed by this fact.

Simply put, you CAN'T conquer the world, you can only live in it. And ultimately, the world will always proffer up more treasures, more disappointments, and more awe-inspiring wonders than this one lifetime or a million others could ever allow you to exhaust.

Actually, I think that's the most reassuring and inspiring thing of all. How awful to feel that you lived in a world where one measly lifetime was enough to explore all its intricacies.

World, I much prefer you this way, frustrations and on-going mysteries aplenty.