Questioning that decision

Let me tell you a little bit about the role Divorce played in my life up until 10 years ago, when I entered into my own marriage contract...
By all accounts (I am the youngest by 8 years, so I've had to rely on my siblings' retelling for much of this) my parents once had a happy marriage. I do recall a lovely home in Mt. Wolf, home-cooked dinners together every night, that sort of thing.
When I was 8 my father moved the entire family to El Paso, TX following a lucrative career opportunity. It also happened to be where his mistress lived, and chaos ensued. My parents separated & reunited a number of times - each one requiring a "fresh start" - and I found myself the new kid at school after school. At least 6 different districts between third and eighth grade - its a bit of blur.
I don't regret any of this one bit, and wouldn't change this family history for the world - its why I start conversations with strangers at the grocery store, why I've been to nearly every state in the country, why I'm good at sales. Its why I love to travel and why I can pack a suitcase like no body's business. Its a huge part of who I am.
The homelife, however, could've been better. I recall alot of slamming doors, broken photo frames, and crying. I was beyond relieved when my parents told me they were getting divorced - I would've been maybe 12 at the time. I loved (love) both my parents very much and it was clear to me that they could not both live happy, fulfilling lives under the same roof. I can remember very clearly the moment when I embraced this lesson: Its better to have happy parents living apart than miserable parents living together. I internalized that almost immediately, and it has informed every decision I've made in my romantic life since that day.
As a child, divorce improved my life immensely. It improved my homelife, my feeling of security in my parents' love...it solidified for me the idea that everyone deserves to be happy, and that they are committing a sin of the highest degree if they don't do everything in their power to make that happen.
Then I got married and had kids.
I had it all figured out. I was NOT going to make the same mistakes my parents did; I was NEVER going to get divorced. I believed that since I knew first hand how much hard work & attention marriage required, I'd be successful at it. I wasn't one of these over-the-moon, starry-eyed brides-to-be you see in the magazines & movies. I was practical.
First and foremost - and I really can't say how conscious this was - I chose a man who I was absolutely certain would never, never cheat on me. Infidelity curse knocked out right there. And I was right; he never did.
Secondly - I didn't fall for that romance bullshit. Don't get me wrong - there were of course warm fuzzies, tender moments - but I chose my best friend.
On my wedding day before the ceremony, my mother pulled me aside to inform me that I didn't "have to do this". Well-meaning, I am sure. My response to her was very deliberate. "Mom, you married for romantic love and look where it got you. I'm marrying my best friend, so we're in it for the long haul." I cannot tell you how many times I've heard those words in my head over these last few months.
I find myself in the unenviable position of questioning that decision every day. Not that I would take it back anyway - the world would've missed out on two incredible children if I had chosen differently. Outside of that, though (always, always outside of that) I wonder: did my marriage veer off course somewhere, or did I choose the wrong road to begin with?