So here is the key, if both parties try to make sure that the others needs are met, then both of their needs will be met and they will be happy. The gospel is that way too. There are a lot of complicated things, but the essential are fairly simple. The things we need to do in order to reach eternal lives is pretty straight forward, but the hard part is just doing them. We do like to over complicate things. We like to concentrate on things that aren't essential but lets keep going on the seminary answers. You know read your scriptures, pray, go to church, help people, fast, hold family home evening and family prayers. I hear people bash them all of the time. Like it is a cope out to give those answers, but they are the standard answers for a reason. They are the path to live with our heavenly father again.
Now back to the happy Marriage. I had one woman tell me "well it takes both people in the marriage trying then?" Yes, one person can't do it alone and it is not easy but it is both simple and possible.