There's a term for a certain brand of sex-life detriment caused by watching porn, Porn Creep...
A condition that results from the constant or excessive watching of pornographic material.It is characterised by an inability to get an erection under circumstances that do not involve the watching of pornographic material, due to the lack of psychologial connection between other human contact and sex. One treatment involves watchin porn until the erection is achieved then having sex, this re-establishes the connection between other people and sex. This condition is more frequent in virgins as the initial connection has not been made.
Urban Dictionary: porn creep
I've heard of that . . .