I'm going on holiday with Helen," I tell a friend. "It's the first time we've shared a room. I hope we don't argue."
"She is very beautiful, you know," my friend warns.
"Yes, of course," I say, puzzled. I know Helen is lovely – obviously she'll look better than me in a swimsuit – but she's one of my favourite people in the world.
My composure slips, however, when several more people mention Helen's beauty as I'm describing our trip. And I do know what they mean.
Helen and I have been friends for 10 years. Before that I'd spent my life trying not to have a beautiful friend – compare down, and not up, as the psychologists say.
At university I'd have run a mile from Helen. A shy, bookish student, I spent days reading novels about plain governesses who had to fight to be seen, and even when I started working as a journalist and my social skills improved, I couldn't help noticing how nice-looking people prospered.
It's this "pretty privilege" that drives me mad: every time you watch a film or walk into an office, there are people in power who are there partly, or wholly, because of their beauty.
Equally I can't bear the word "ugly", or when people are rude about the appearance of others. For me beauty is political – influenced by your parents, where you grew up, by money and genetics. It's not a gift that's distributed fairly.
I've had a few late-night debates about this with (good-looking) friends. When one told me, "But I like beautiful trees, why can't I just surround myself with pretty people?" it nearly ended our relationship. So when I first saw Helen at a fashion party when we were both in our 40s, I wasn't especially keen to meet her.
She gatecrashed. The party was held near her flat and she insisted the noise made it impossible to sleep. I remember watching this blonde woman march up to the PR. "Hmm," I thought. "She's a piece of work." I made a mental note to avoid her.
But to my amazement, Helen came up to me and said: "You look as if you're over 38 and have something to say for yourself." She gestured at the room of gorgeous 20-somethings and grimaced.
That was it, we were off. We talked, danced and put the world to rights.
Since then, I've gone on trips with Helen and her husband and daughter, sunk illicit cocktails and seen her "off-duty" without make-up. I love the way she is kind to waiters and shop assistants, and is always punctual (unlike me).
When men get too attentive, she waves them in my direction (funnily enough, they are not always as smitten by me). I do notice women checking out Helen's appearance. Mostly they're amazed at how friendly she is, though an envious friend once asked: "Helen is a secretary, isn't she?" Actually, no, she heads her own music recruitment business. Clearly the "pretty privilege" can also invite prejudice.
Anyway, I know how much work it takes to look like Helen – she exercises with a trainer, eats sparingly, takes great care of her wardrobe. And over the years I've understood she has vulnerabilities, too. They used to call her "wax work" at school because she was too well made-up. Adopted as a baby, she adores her parents but knows how it feels to be an outsider.
Being friends with her has taught me a grown-up lesson. Yes, beauty gets you into the room, but after that, you're on your own. It's hard work and kindness that really propel people up the ladder.
As for our holiday, I'll pack my most flattering swimming costume, get a spray tan and a blow-dry and blitz Pilates before we go. But my greatest asset will be my lovely friend.
This article appears in Sunday Life magazine within the Sun-Herald and the Sunday Age on sale December 9.