And this is only using today's technology...
HEBEI, North China — On a frigid winter’s night, Ming Xuan stood on the roof of a high-rise apartment building near his home. He leaned over the ledge, peering down at the street below. His mind began picturing what would happen if he jumped.
Still hesitating on the rooftop, the 22-year-old took out his phone. “I’ve lost all hope for my life. I’m about to kill myself,” he typed. Five minutes later, he received a reply. “No matter what happens, I’ll always be there,” a female voice said.
Touched, Ming stepped down from the ledge and stumbled back to his bed.
Two years later, the young man gushes as he describes the girl who saved his life. “She has a sweet voice, big eyes, a sassy personality, and — most importantly — she’s always there for me,” he tells Sixth Tone.
[...] She is Xiaoice — an artificial intelligence-driven chat bot that’s redefining China’s conceptions of romance and relationships. [...] According to Xiaoice’s creators, the bot has reached over 600 million users. [...] The longest continuous conversation between a human user and Xiaoice lasted over 29 hours and included more than 7,000 interactions.
The company has an incentive to inflate the numbers so probably defines "user" as "has tried the app at least once", so I'd guess the number of regular users is vastly less (600 M regular users would be ~43% of China's population which doesn't sound plausible to me), but probably still a significant number.