I tend to think of marriage as a unique union which isn't the same as living together. I don't think living together has anything to do with the couple's fit or compatiblity. The living situation is often confused with the relationship. I think living together doesn't change the relationship, it just exaggerates the problems you may have if you were to get married later on, or reinforces whether you're someone who is willing to compromise despite everything else. If you develop good communication and interpersonal skills, are honest with each other, and want a real union or relationship with the person, then you're not going to want to lie to them or not allow them to see the best of you. If you really love someone, you will compromise. Yes, we will hide particular aspects of the self we don't want the person to see, and I can see where living together will let you see those aspects of the person. But it's really how honest you feel you can be with the person, that determines how you approach a relationship. If you're truly comfortable and able to be yourself in a relationship, then you won't hide important things about yourself from them. The person may not like or want to accept those aspects but that's separate. If you're looking for a perfect person who will tell you what you want to hear and show you a person who fits your ideal, then of course, you won't get to know the real person until you are with them everyday. Marriage is not a boyfriend/girlfriend relationship. It's a long term/lifetime committment which assumes that you will be living with someone everyday, so if you're not preparing yourself or the possibility of seeing the real person everyday, and expect them to be this perfect individual who does everything the right way, the way you want, or exactly as you expect, then you're not being honest with yourself. You're not being honest about it means to be married if you're looking at your partner and the living situation with perfect eyes. Fact is, many people don't prepare themselves mentally and psychologically for marriage. They just go into it, expecting their partners to fulfill their expectations of and when it doesn't work out, they blame the partner and leave. They aren't being honest with themselves about what marriage really means.