Problem with a hysterical woman,?

In back of our yard there is a overgrown brushy area an yesterday we were sitting it the back yard. She suddenly seen a black snake approximately two, six inches long and panicked! She has this thing about being afraid of snakes that is out of proportion to reality and stayed awake all night last night watching for "that snake to come in the house"! Other than this quirk she is sane and rational. Any senable advise appreciated.