It was the destination wedding to end all destination weddings.

Just outside of Dublin, on 560 acres of emerald green countryside, sits a castle dating back to 1420. Queen Victoria stayed there. More voguish royalty, Sir David and Victoria Beckham, were married there. Now it was time for a new couple to fall beneath the castle’s spell—along with approximately 100 people who loved them enough to come from all corners of the planet to share their enchantment.

And enchanted it was: The bride could not have been more beautiful, and the groom looked properly awestruck as he watched her approach, tears coursing down his cheeks. Every last detail of the ceremony flowed in perfect synchronization, without feeling too regimented; nothing had been left to chance except the weather. Normally, Dublin in May is a dicey time for an outdoor event, but on this day, even the sun couldn’t resist spying on the proceedings. It shone so brilliantly every guest seemed to glow from within.

I was one of those guests, and, yes, I suspect I was glowing, too. I was certainly keenly aware of the sun. I hadn’t worn a hat, assuming the day would be chilly and, most likely, the ceremony would be moved indoors. But no, if anything, the sun grew stronger every minute. Despite a generous slathering of SPF-50 sunblock, I could feel my face begin to burn—especially the areas on my nose and hairline that had previously been assaulted by cancer.

But what could I do? The couple had not even begun to exchange their vows, and I was seated right near the front. One doesn’t sneak out in the middle of a wedding, no matter how much one might blister afterwards. And I really wanted to stay—the ceremony was so lovely, the setting so blissfully right. I stuck a Kleenex on my nose and prayed for a passing cloud to shelter me.

When the groom at last had kissed his bride, I made a beeline for the nearby library, where drinks were being prepared—not to indulge in the champagne, but the shade. Out on the lawn, all the guests were milling about, congratulating the newlyweds and their families. It was the right and proper thing to do, and I knew it. One must share one’s delight with the bride and groom. But the couple was out there, in the blistering sun.

The sound of 100-plus guests and a nearby chamber orchestra began to fill my ears not with a joyous noise, but with a buzzing that felt suspiciously like that sound you hear when you’re about to faint. I’ve often wondered if my bipolar disorder—which makes my life so intense emotionally and sensually—contributes to my frequent bouts of overstimulation. I know that research has shown that bipolar disorder impairs “sensory gating” (the brain’s ability to regulate its sensitivity to incoming stimuli). I also know that many of the psychiatric medications I take can cause extreme photosensitivity (an exaggerated reaction to sunlight, which I already have as a redhead).

But what good did all that research do me now, when life had turned too Technicolor for comfort or for safety?

My partner Colin was out on the lawn with the rest of the guests, watching a display of trained hawks and falcons (every well-appointed wedding must have a falconer). There was no one I could turn to, nothing to do but either faint or sit out the rest of the festivities in the cool, empty library. A large leather armchair by a bow window beckoned. It would allow me to see what was going on outside but stay shielded from the sun. I sank into it gratefully and decided to spend the afternoon there—ignoring Miss Manners and wedding etiquette and anyone else’s needs but my own.

This was extremely hard for me to do. Ever since I was diagnosed with bipolar disorder, I’ve struggled to pass for normal. I want to appear to be functional like everyone else—never letting my mental (or physical) limitations make me seem different from the rest of the crowd. But that day, I said to hell with it; right now I need to be different.

Selfish? Maybe. Rude? Perhaps. But like so many of the best moves I’ve made in my life, this decision came out of sheer desperation. I didn’t stop and weigh all the options, or ponder what was proper and right. I simply took care of myself.

It was the best part of the wedding for me, a destination I needed to reach on my own. A while after I’d settled into my space, a young man who’d wandered in for a drink came over and asked me if he could take my picture. “You just look like you belong here,” he said. I knew exactly what he meant.