actually, it isn't too different. In the initial courtship, its pretty much the discovery. And alot of the communication that keeps us interested is really getting to know each other.
But, with a family, its different. We are in a much different stage of communication. With a lifetime partner, its pretty much the same, you will reach a point where most of the discovery is already done. If you find a soul mate in your spouse, the communication is natural. You cannot really focus on the talking. Its about being comfortable enough to relate, share and be yourself. IF the both of you are not expressive and don't talk much normally, being yourself isn't going to change that much. You probably will not need or appreciate that kind of 'non-stop' talking needs of another couple. Also, communication isn't only in the form of physically engaging in a conversation. A lot of communication are actually non verbal. The disagreement, anxious, resentful, flirting, fun, cheeky, loving signals are all sent mostly through our actions than the talking. We focus a lot on the verbal without realizing how much the non verbal body language actually impacts the context and mood of it all.
Lastly, I agree with Junkie, work on the sparks to sustain the relationship. u need to keep the attraction and romance going. Somehow, that is lacking right now. Many times, I don't need to say much. I just look at my wife with admiration and attraction. A simple silly grin at her or stroke of her hair or a hug. It speaks a lot between the both of us.