Just to start off, let me say I am Pro-marriage. I believe that if you can get your marriage back on track it is better for everyone involved. This includes the couple, the kids, and family members from better use of time, money and emotional stability of all involved. That being said, it is up to you what your intentions are when entering counseling. I believe most couples can make progress and improve their marriage if the really desire that goal.
Most likely, your marriage has slowly become the way it has over time. Rarely, people wake up and are instantly unhappy with their marriage. It's easy to get off-track. Life happens, you get busy with your careers and the kids... maybe you need to spend some time re-affirming your commitment to each other. The goal is to identify the patterns that cause marriage problems and help you make changes to improve your relationships.