One moment Walt is training for the biggest fight of his career, probably really enjoying life, enjoying every day. The next, he is plunged into a living hell, the absolute worst suffering a person can go through.
It is extremely difficult to come to terms with the brutal unpredictable nature of life, how things can change so quickly and in the worst possible way, and no matter what changes, we're never even a single step closer to understanding why. The pain in which Aniah's family is currently going through is impossible to understand. It's all so unfair.
RIP, and my warmest thoughts and love go out to the family.