In a good marriage, you never have disagreements, er, fights?

Just remember when you are reading this hun, I love you...
This is not a revelation to the married masses out there, nor is it a caveat for those single and eyeing up marriage in a society where, unfortunately, more than half end in d-i-v-o-r-c-e.
My wife and I sometimes disagree and in some instances it escalates into a fight, as tension ratchets up, voices are raised and we either stand firm, arguing our position or offer a half-hearted apology for words that came out in a manner that "wasn't what I meant."
What follows is minutes, or even hours of sullen silence, broken only by the sounds crackling from the TV or one of us talking to our pug, Stella, who, by the way, can do no wrong. Even when she does, well, my wife's reasoning is that she doesn't know better because "she's just a baby."
C'est la vie.
How does one reconcile himself to the reality that fights are inevitable - and perhaps even healthy, cleansing if done correctly - and not something to feel bad about?
I love my wife, and she loves me. This much I know. Neither is perfect and even though I may try and justify my words and/or actions in the midst of an argument, I try to keep sights on what is most important: that life is short, I am lucky to be married to someone who makes me laugh, shares my thoughts on many things, is a great cook, an independent woman with a great sense of humour has a great fashion sense and in the midst of a South Okangan winter, looks terrific in hats, boots and scarves.