Never been married, but ...
... if you don't know after one year, you'll never know. If you've been dating 2-3 years, the last two have been a waste of time. What more do you need to know? There's not gonna be any little quirks she's hiding. You've done it all after a year, time to sh-t or get off the pot.
I'm amazed how much time people waste on this process. Plus, think of all the women you can't date while you're doing this prolonged "dating."
Cyrano took me to the woodshed on the other board for my timeline, but it's true. It's just a complete waste of time after a year. If a woman doesn't want to get married after a year of dating, time to move the h-ll on.
Remember, there are 100's of thousands of women you could fall in love with on this planet and the only reason you're with the one now is proximity and timing. If you didn't live in X town you wouldn't be with X girl and so forth. No fate or soul mate B.S., just cold, hard facts.
After two years, you don't know? No reason to keep test driving the product. It obviously doesn't work for you or her.
My suggestion? Start dating almost anything with a pulse every single week. Go for a goal of dating about 25-40 women in one year to find out what you really want. Also, when not dating, hang out with some fellow DJ's and get some male perspective on life.
You've been dating this broad WAY too long.