His family has said that he went dark on social media starting the 18-21st of Feb. He also had issues with substance abuse apparently, but who knows.
That said, I think it's inappropriate to speculate, particularly when the circumstances likely involve mental health. We should really just celebrate Adrian and send our best to those who survive him, as well as take the opportunity to mention that mental health is extremely important in our line of work (and not!) and you should never feel bad for seeking help or fall victim to the stigma. Code can wait; you and your brain can't.
Tragic loss, way too young.