3. "When we're married/have kids…"
It's natural to fantasize about wedded bliss and the three kids you and your beau will one day spawn — you're only human. And sometimes you might even entertain this fantasy very early on in a relationship. But unless you want to scare him away permanently, keep thoughts like these in your head where they belong.
Even if he himself has thought about your happily-ever-after future, he probably doesn't want to hear it described out loud just yet. Wait until you're sure you're on the same page regarding marriage, kids, and the future of your relationship before you start prophesizing. A gut feeling probably isn't good enough.