I was asked what one thing I would tell couples for a healthy relationship:

I married my best friend. Cliche', I know, but it's true! We were high school sweethearts and spent our dating years fishing, off-roading and dreaming of being rock stars. Our wedding was exactly three weeks after my eighteenth birthday. Three jobs, two houses and one child later, people are asking how we do it. Often they just blurt out, "Eighteen, what were you thinking?!" and many are surprised we've made it this far.
Truthfully, many things make our marriage work. The usual, honesty, commitment, kindness, pray together, don't let the sun go down on your anger; all of these are truly important. One thing our pastor stressed was the importance of knowing and communicating our expectations; he wasn't kidding! Also, we were fortunate enough to have an older couple dating while we were who held us accountable. This assured that we built a foundation on true relationship rather than just physical intimacy. All of these things are very important, but whenever I'm asked, "How on earth do you guys do it?" the first thing that comes out my mouth is, "We fight well."
I say it with a smile that often confuses people. Arguments aren't generally something to smile about, but it's true. While we were dating, we learned how to fight. To pass on what I've learned in my years of argument experience, I summarize it something like this. Disagreements are guaranteed in any relationship, but you have to learn to care about your spouse before yourself. I would say 98% of our fights grow out of a selfish attitude. Fortunately, 100% of them end because one or both of us chooses to have a selfless attitude. Secondly, you never fight to win. If your spouse walks away feeling like they "lost" in a disagreement with you, you're the real loser. And lastly, figure out exactly why you're arguing and the best solution possible. Sometimes this requires one person to bend farther than the other. A selfless attitude is a must here! This is especially true when you've compromised in the last five discussions and you really think your spouse is wrong this time! Take a deep breath, what's truly important here?! It's even ok to agree to disagree on some things. Obviously this doesn't work with serious issues such as what state you'll live in. However, there are many times where an agreement isn't reached, but you can both walk away with a good attitude by leaving it that way (even if you have to revisit it later).
So I guess what I'm saying is that I wouldn't consider love a battlefield, but it certainly comes with its share of clashes. Fortunately, a humble and contrite spirit can assure that everyone survives!