Why does he break down in tears after the fire?

The author witnessed the loss of his house and the belongings, everything turning to ashes in just a few moments. The fire was such that it took the fire fighters around five hours to put the fire away. In this mess and loss, the author lost his cat. It was nowhere to be seen, either it ran away or it died in the flames of his house. He considered himself responsible for all the loss and broke down in tears and cried and cried.