At Mass today the priest said something about the Gospels of today and tomorrow that I liked a lot. It was about connecting the miracle of the loaves with Jesus walking on the water. Matthew recounts both these events right after the death of John the Baptist. So Jesus is mourning John's death, and he wants to go away by himself to pray. But the crowds follow him so he changes plans and feeds them. Only after that does he dismiss the crowd and find the time to pray. In that prayer, he somehow came to terms with the death of John the Baptist and in prayer faced the reality of his own death. Then he came down, and met the disciples while walking on the water. That miracle of walking on the water is symbolic of Jesus as the conqueror of death. Perhaps Peter fell not only because of his lack of faith, but because his lack of faith meant he didn't yet understand the mystery of death.
For some reason I liked this interpretation a lot. It has much to say to people who are mourning the death of loved ones. Even Jesus mourned for those he loved; we also see that when he cried at Lazarus' tomb.