My deep interpretation:
He was a man who had lived his entire adult life in a very structured, safe and mundane way. He took much of life for granted; his wife, his daughter, his job, his home. The loss of his wife and then his retirement triggered a need for understanding and learning of basic skills that had always been done for him.
His crying can be interpreted as a "rebirth" in spirit. He was learning what life was again, just as a child does. He took pleasure in the simple things, finally, just as a child does. When you get to that point, a beginning and an end of your life, a beautiful flower or star filled sky can make you cry. You cry for what stirs your soul and for the time you wasted by not living life to it's fullest and not telling those you love what you feel.