Why is it important to have personal space in marriage? Too much of good thing is bad, right? Even though, the couple can be in love with each other so much and can tolerate each other only to certain extent. There is no perfect person born yet, everybody has their own flaws. Sooner or later can get tired of each others imperfection. Also, "Home" is a crowed space, no where to hide, if you are upset/angry, you need time to cool it off. How to create that space? It depends on what phase of life you are in now - just married, no-kids, young kids, grown up kids, empty Nester. If you are at just married, no-kids, empty Nester stage - see each other on the anniversary day to avoid any misunderstandings. Just Kidding..... Every couple is different. Having a network of friends and hobbies are important. Hobby, I meant anything other than, with 'flashing lights' - computers, video games, TV, mobile phone. Key factor: Human interaction is important for the sanity of the person. From my personal life and growing up watching dad/mom, men may need to be left out alone before the work and few hours during the weekends to sync up with their 'boys' network. Probably, that is their thinking time or relaxing time before the work day and catching up with their network during the weekends. Does it applicable to everyone, may be not. Myself, I am a late sleeper and my DH likes to hit the sack early at night. I leave him alone in the mornings and he let me have few hours to myself at night. So, it worked out to be fine between us. If you have young kids, there is NO "me time" in life. It will be the time, you can sleep without any disturbance. If you have grown-up kids, may have to take turns to have that "me time". What kind of problems can be avoided by making that space? Having that "me time" or the personal space gives that needed break from each other. After having few hours away from each other, the minor friction that they may had earlier no longer matters. Otherwise, the little thing may look like a mountain sized issue. It is a human tendency, suppressed anger blows out of proportion.