Prepare yourself for an orgy of unbridled self-pity and loathing. I'm not proud of the person I've become: because I'm everything you predicted I would be. Callous? Maybe I'm just over familiar with misery, panic and pain. People don't die every day (although the manager in the mortuary thinks he's being pretty funny when he calls me Dr Shiplake), but if they're not ill and in intractable pain, then they've been abandoned by their families, or they're desperate to be discharged, and there's never much I can do apart from smile, which I am doing less and less.

I am gradually, regrettably, ceasing to care. I bet the man who runs the roller-coaster at Alton Towers doesn't get scared when he goes on it for the 100th time. But I feel like I should be involved in my patients' pain, and the relatives do too: if I'm not concerned, if I'm not astonished and aghast at the sheer scale of their appalling ill-health, to the point of devoting myself to 24-hour bedside supervision, then they take no trouble to share their disappointment.

Part of the problem is, of course, that I am just so busy. "What was the result of that test my father had yesterday, doctor?" people ask, quite reasonably. And the responses that spring into my head are, in order of shamefulness: "What test?", "How should I know?", and "What's it got to do with you?". And when I'm not cursing families for pestering me, I'm cursing them for dumping their grannies on the doorstep.

Which brings me onto Christmas, and my own special appeal. Don't dump your granny on me this Christmas. In fact, please could you try especially hard not to dump them on either Christmas Eve or December 27: the days when I'm working in A&E. The 27th, it might amuse you to know, has been statistically demonstrated as the worst day in the year for granny-dumping, and will be particularly horrific coming after a long weekend with no GP surgeries.

And all that anyone ever wants to talk about is medicine: my friends, my mum, even my patients. I wandered into a patient's room for a quick chat the other night, during a quiet moment on ward cover, and all I was seeking was a bit of solace and a quiet moment. I even offered him some lemon cordial: he's a nice guy, we get on well, and he has a rather good collection of old films on video. But as soon as I get in there, all he can talk about is his endless afflictions.

The thing I'm not telling you is that I just want to get out. I don't have the nerve, the commitment, the staying power, the moral reserve, the social skills, the competitiveness, the caring nature, the backbone - I just don't have any of that stuff you need to be a doctor. I feel awful at least 10 times a day, I cry at least once a week (and I'm a boy). I tell my senior house officer and all she can do is smile and say, "You'll feel like that more than you can ever possibly imagine, for years and years."

What do they think they're all playing at? They're all either heavy drinkers, or compulsively unfaithful, or addicted to the gym, or in one case masturbation (a drunken confession). Doctors talk about the poor lifestyle of hospital medics as if a good lifestyle was something slightly camp, or incidental, or disposable. But junior doctors have no lifestyle, outside of being doctors, and most of our patients are geriatric nightmares with nothing more than social problems, getting more and more unwell the longer they spend in hospital.

So think of me and my inexcusable self-pity when you're having fun this year around the Christmas tree, and remember our special appeal (Terry Wogan children-in-need voice, stirring music, soft focus footage of old ladies gamboling gaily in the garden): "Keep them at home this Christmas."