New month, new day, new questions.

    Every day in this phase of life I'm coming up with questions that need to be answered. One of the biggest ones is obviously figuring out exactly what marriage is. I realize that while I've always considered being married, but never given too much thought as to what a good marriage should be. Needless to say, we're figuring it out. I know that I always thought I wouldn't want to live with someone until we were married, but Chris's proposal of moving in during our engagement has turned out to be wonderful. I haven't lived with anyone but my family and one unfortunate stray we let in since college. Now Chris and I have the chance to figure out exactly what each of us needs in a nice cozy 1 bedroom apartment. I'm learning what our marriage will be, and how to talk to him when I'm unhappy rather than just going to another room. It's not always easy, but I love it. Even when we have a tough time it ends up as a learning experience and we always seem to go to bed happy.
    A question that has come up recently (today actually) is how could a relationship that is built on lies survive? I'm so compulsively honest, especially with Chris, that I don't think I could possibly live day to day if I was keeping secrets from him, let alone actively lying to him. I understand omitting the occasional incriminating detail in the beginning of the relationship. Maybe we don't want our significant other to know just how many other people we've been with, or just how bad we've been in the past. We grow and change, and perhaps we want this new relationship to be a part of this "changed" us. I suppose it could be understandable. I'm lucky in my relationship with Chris, if for no other reason then I tried to scare him away from the start with the truth. I wasn't looking for a serious relationship, so I figured telling the complete truth right away might make him reconsider what he was getting into. It didn't work.
    My relationship aside, isn't there a point where you have to be honest or the relationship has to end? If you go on lying for a long period of time, wouldn't that in and of itself cause the relationship to end? Especially if you are lying about big, important things. If we lie about things, like being sick for instance, having something like a mental illness or an STD like herpes that doesn't necessarily show symptoms, at some point our partner will have to find out. Now I'm not talking about casual flings or one night stands (although if you have something potentially contagious you should always inform your sexual partners), I'm talking about relationships. At some point you'll have a slip, show a symptom, or their own inquisitiveness will bring them to notice something going on.
    Why would a person set themselves up to damage a relationship that they've built. It seems obvious that someone would be lying to their partner due to fear of losing the relationship if their secret was found out, but when the secret inevitably surfaces won't that damage the trust and put the relationship in jeopardy anyway?

Even with 5 years of studying psychology there are a lot of things I don't understand about people.