It is a chilly October evening in 2021 that Adam Becket remembers most sharply. He was 26, and had moved to Bristol a year earlier to start a "dream job" in the race cycling industry. So far, he had struggled to make friends.

"I wasn't alone all the time, but […] I was a bit of an outsider," he remembers.

As he headed home, the streets were full of Halloween partygoers in monster and cat costumes. "I walked past people turning up to friend's houses, people running into shops to buy beer.

"All the pubs were full. It just [felt] like a different world that you're not part of. And you feel like you can never be part of it."

That night, he felt like the only person experiencing serious loneliness. In fact, it is becoming a defining feature of his generation.