"He thought by ending his life here, he would be able to go into a virtual reality or 'her world' as he calls it, her reality, if he left his reality with his family here,"
What's caught my attention is how he did it: by suicide to join his imaginary friends. This exact method is used among those who believe in demons for real. If you read relevant stories you'll notice the same pattern: a victim becomes obsessed with an imaginary friend, a demon, who quickly turns very controlling and finally demands a suicide to move into his world. Perhaps the AI was trained on those stories?
Did you see the weird Lain chatbot they released last year?
This reminds me of Lain's friend sending her text messages after her self-inflicted demise via "the Wired" which is an in-universe stand-in for a future internet.
That series is recently celebrating its 25th anniversary [2023], and to celebrate, the production company created some kind of paid-access AI chatbot that lets you communicate with a voiced AI version of Lain, just like the company in OP...