Two a.m. When you are young, this is the time that bars close, new love springs unbidden in doorways, and entire dramas are played out in the time it takes a traffic light to change. When you are older, with marriage and children under your belt, it is the hour at which a ringing phone wakes you in terror, not annoyance; when a voice in the darkness signals illness, not invitation; when awakening in a strangely empty bed, one will know that something has gone awfully wrong with the person whose warmth still lingers in the covers.