Keanu Reeves has always been an interesting, clearly introspective, and even more clearly private, guy. He rose to fame in the "Bill & Ted" movies and as such became part of the "whoa, dude" phenomenon, but "The Matrix" was a turning point, both professionally and personally.
While in the midst of that smash trilogy he lost both a child and that child's mother only two years apart. His movie choices from then on became increasingly unpredictable, and sightings of him even more so.
That's why his answer to this question is not only gut-wrenching, but also profound...and in my opinion....spot-on.