Is it permissible for spouses to think about each other sexually while they are physically apart?

It is permissible for spouses to think of each other, with the necessity of observing that a Muslim should not be absent from his wife for more than six months; due to what this may lead to in terms of falling into temptation and the whispers of Satan. And perhaps thinking may lead to arousing desire and falling into forbidden acts. A Muslim must break the dominance of lust through fasting, lowering the gaze, avoiding temptations, and fearing Allah Almighty. Likewise, it is not permissible for a woman to describe another woman to her husband as if he were looking at her.