Another thing to note is that a good couple isn't one which never has arguments, but rather one which resolves all arguments. No grudges, no lingering anger. A mutual understanding, even if it reveals a difference in ideas.
I had at least one instance of conflicting ideas with my significant other, but we figure things out and set any disputes straight. Discussions usually end with an agreement and a solution. Even if they don't, we don't end with "fine, be like that", but instead with "I love you" or "There's nothing wrong with having a different opinion". Maybe it's just me, but I think a perfect couple doesn't even remotely suggest a completely similar set of ideas and beliefs between two people.
Sometimes it's nice for someone to disagree. It shows individuality.