Watching a podcast about eternal identity, something that really stood out to me was the concept of “not being alone” as to marriage; Satan had to find Adam and Eve alone to more easily tempt them.
Hugh Nibley said: “[Satan's] first step (or wedge) had been to get one of them to make an important decision without consulting the other. He approached Adam in the absence of Eve with a proposition to make him wise, and being turned down he sought out the woman to find her alone and thus undermine her resistance more easily. It is important that he was able to find them both alone…” 
This doesn’t mean that husband and wife have to be constantly at one another’s side. I think that would drive us all crazy! It is, however, very important that husband and wife are “together” both spiritually and emotionally.
Elder Oaks said: Satan's most strenuous opposition is directed at whatever is most important to the Father's plan. Satan seeks to discredit the Savior and divine authority, to nullify the effects of the Atonement, to counterfeit revelation, to lead people away from the truth, to contradict individual accountability, to confuse gender, to undermine marriage, and to discourage childbearing (especially by parents who will raise children in righteousness).
If one of Satan’s “most strenuous oppositions” is targeted “to undermine marriage”, this shows me how extremely important it is to be one with my husband.