The Good Mother standard: Can anyone live up to it?

Mother Earth. Mother Mary. The "good mother." Is there a more impossible standard than motherhood itself? Every culture seems to believe in a mother who is endless. Endlessly patient, endlessly giving, endlessly present. In Christianity she's Mary, the sinless virgin, the giving and eternal mother of the church. In psychology she's the "Good Mother", always available and calm, never faltering. In…