"You are going to get a certain amount of snarkiness on the Internet no matter what, and my rule is that you don't post anything that you wouldn't say to someone's face." Marc Andreyko (Writer of DC Comic's "Manhunter")
I say live together for at least a year first. A brief mental survey of the divorce status of my friends in their 30s & up indicates that as a minimum criterion. I would respectfully, but strongly, disagree with Emma on this.