Last Sunday my brother had his 40th birthday lunch in an Italian restaurant. As our starters arrived, I glanced across to the table next to us and spotted a young woman who I’m pretty sure was suffering from anorexia.

I hate writing that – “pretty sure was suffering from anorexia”. As though thin women aren’t constantly being over-diagnosed by ignorant observers who know nothing about the inner lives and fears of others. Celebrity magazines are the worst for this; one week a young starlet is in “size zero hell” (usually because she’s breathed in while wearing a bikini), while the next she’s “flaunting her curves” (having breathed out again). I don’t want to make these pathetic, faux-concerned assessments of others, especially since, when I was anorexic, I was paranoid that everyone else in the entire world had an eating disorder, too (at least I think I was paranoid). All the same, something about this particular woman really struck me. It was her face rather than her body. Pinched and haunted-looking. Her eyes looked so dead. She seemed so lonely amidst all the food and conversation. She looked cold and scared, and it reminded me of a fear that sometimes I’m able to forget. And then her order arrived. It wasn’t quite as she’d expected it to be. She questioned the waiter, her voice rising, this mix of nervousness – she didn’t want to cause a fuss – and terror – she had to say something, absolutely had to. I was afraid she’d cause a scene but she didn’t, eventually backing down. She ate only the garnish of a meal that perhaps she’d been planning for several days. Throughout it all her hollowed-out hands were shaking.

It is hard – perhaps impossible – to convey what being anorexic is really like. There are plenty of autobiographies written by anorexics, but I tend to avoid them. The impulse to write one in order to educate others might well be sincere, but I’ve always found something amiss in the execution. I can’t help detecting another urge – a desire to keep the disease alive, to immortalise extreme thinness in print. And because when you’re reading these books you can’t actually feel the hunger and cold and sheer isolation, it draws you in. Whatever nightmares are being described, they never sound all that bad, not when emaciation is the reward.

Yesterday Lady Gaga – who has put on weight! – posted a picture of herself on her Little Monsters site with the caption “bulimia and anorexia since I was 15″. The picture – herself unadorned in underwear – and her urge to respond so personally to tabloid attacks impress me. There’s an immediacy that one doesn’t usually find in “my pop star eating disorder hell” retorts. Usually all one has are words. Bulimic, anorexic, pop star, singer. How many people who haven’t been there understand? How many people can imagine someone like Gaga hunched over a backstage toilet, one hand tooth-marked, smeared with vomit and bile? Or praying for an interview to end before the laxative overdose kicks in? Or posing in a meat dress but thinking only of the next can of diet coke, the next piece of chewing gum, and how long these things can be made to last? (I’ll be honest – I haven’t a sodding clue what the pop star lifestyle is like – but I do know what it’s like to have anorexia and bulimia. I can’t imagine superstardom can do anything to take away the mundanity and humiliation.)

I haven’t always been a fan of Lady Gaga. I don’t think her music is particularly original. Her eccentricity has always seemed a bit too stage managed to me. And then there’s that mega-annoying chapter comparing her and Jordan in Caitlin Moran’s How To Be A Woman (not that that’s Gaga’s fault, but still – it really rubbed me up the wrong way). Even so, the way in which she’s positioned herself against the tabloids and their mocking – shown herself in a way which is apparently “unflattering” and invited others to do so, called for a “Body Revolution”, told others not to feel ashamed – has actually really touched me. I have joined her Little Monsters site and honestly, the way in which she’s challenged people for their lack of compassion while remaining willing to expose herself has made me feel better about myself, and it seems to be having this effect on others, too (as in they feel better about themselves, not about me. But they’re welcome to do that, too). Little Monsters actually feels like a very safe, humane space, in which human flesh isn’t hated simply for being there. In the mainstream media such a thing is rare.

I hope that the woman whom I saw on Sunday can feel free and happy, however she looks. I hope other people – those who “don’t look ill” but who nevertheless wage war on themselves and their “curves” – can achieve that feeling of freedom, too. I know that I am not fully there myself yet. Still, if slightly naff, hero-worshipping but surprisingly sincere pop star websites prove helpful in getting me to where I want to be, I’m sure as hell going to use them.