Honestly, you get out of it what you put into it. I've got 20.5 years thus far, and going strong. I guess we're both too stubborn to quit!
The only things my wife and I laid down before we said "I do" was that there was no escape clause, and how many kids (she wanted 12, but I knew she'd change her mind), and how we'd eradicate that problem once we hit the target number. We've had our struggles and knock-down-drag-outs, but we've made it through.
I hope the same for you. Just let her drive... I've seen what happens when yo get behind the wheel.