On a sultry night in late July, a friend offered to introduce me to a guy she thought I'd like. "He's tall, smart, and funny," she'd said, and as an afterthought, "oh, and a little depressed. He's just out of a bad marriage."

"No thanks," I told her. "The last thing I need in my life is a depressed person."

She persisted, and so I met this man in a friend's living room. We spoke easily to one another about Life magazine, and Walter Hudson, the 1400-pound man who was too big to get out of his house. She was right: He was really smart. And awfully tall. Still, I was wary.

A week later, the tall man asked me to go for a walk on the beach. Again the conversation went easily, and he made me laugh more than I had in a long time. He was so comfortable to be with that I decided the two of us would become great friends. Having dated only difficult men, it never occurred to me that you could actually date and talk and laugh at the same time.

Over Labor Day weekend, he invited me to go on a bike ride with him. We pedaled through the countryside for about two hours. We stopped at a farm stand and bought a bunch of zinnias. We sang old camp songs, and, most of all, we laughed. Back on the main highway, we rode single file. I followed close enough behind him that when his front tire got stuck in a pothole and his bike slammed to the ground, I couldn't slow down enough to avoid crashing right into him.

Time slowed down, as it does during crises. I envisioned myself plowing into him; my head cracking open; blood on the highway; broken ribs, knocked-out teeth. As I mentioned, I'd been through a bad spell and my thoughts inevitably ran to the apocalyptic. But mostly I thought, here goes again. I am spreading my toxicity; I am unfit to be with anyone.