I do not know much about this topic actually, however I would say I think that masturbation might have an emotional effect if you are emotionally depressed, or insecure. On the other hand however having sex with your wife, gives you to intimately understand that you are loved, wanted and supported. And somehow brings comfort, which masturbation rarely brings!! Another aspect is a probable unconscious trigger that would possibly give you an impression that you are "being unfaithful" as you are not with "her"(is not always true). I understand your type of stress as a possible actually indicative of a disturbing event in the past which lead to an an emotional insecurity, trying to express itself through excessive sex. You must deal with the little hurt child in you who is crying out for emotional support. Best Wishes, The Friend.