When Duncan and I were engaged, it was highly recommended that we do a marriage preparation course. In the five week course, we sat down with our pastor and discussed hopes, expectations and things we should speak about with each other which we may not have thought to mention.
As beneficial as marriage preparation was, it could never fully prepare us for marriage. You see, when a couple is dating, they tend to only see what they have in common with each other. Rarely would you hear a dating couple say, "We disagree on so many things," as if this is a good thing and still remain together.
After our wedding, we soon discovered how much we disagreed on, and how much we DON'T have in common.
I don't think is a huge problem in itself; what matters is how we face those subjects of disagreement and work through them. From talking to other married couples, I have resigned myself to the fact that this is normal. It's what happens as you get to know another person really well. Duncan and I will keep on getting to know each other better 'til death do us part, and more issues of contention will inevitably pop up.
I think there are particular questions dating or engaged couples SHOULD ask each other before they consider taking the next step. One is whether or not they want to have children, or if one partner knows they cannot have children. I know of a few relationships where this has been a major source of conflict, and the partner who wants to have children (or have more children if it's their second marriage) feels deceived because they assumed their spouse agreed with them.
But there are also many questions which we never, ever thought to ask each other, and after randomly mentioning something in a conversation, were shocked to discover we disagreed on some issues. One was the public vs Christian education debate. Duncan grew up attending a 'closed' Christian school (where only children with at least one Christian parent can attend) for primary school. I grew up non-Christian and spent my entire education in the public system which worked fine for me. Duncan wanted to send our future children to one of those closed schools and was shocked to find out that I despise them with every breath I take. I simply do not believe in taking children from Christian families out of the world as if this will some how stop them being sinners and hanging out with those awful non-Christian kids. But because Duncan enjoyed his time at his school, he was all for it. I ended up thinking that it was so ridiculous that we were arguing about this when we don't have any kids! Nevertheless, it's a dilemma we'll have to face in the future and a prime example of things couples often don't seek to find out about each other.
I really don't think there is any way around this. Marriage is a journey of discovery and sometimes, when the issue is not important, we've had to agree to disagree, focus on the things we have in common, and move on.