why i ' m a bad girlfriend but a good friend

So last night I went out with my girlfriends and one of the many topics of conversation is when the heck are John and I going to get married (don't act like you haven't thought about it too...it comes up often...I have no answers).  My friend Court said, "how long have you guys been together anyway, five years?" I said, "no three."  But that didn't sound right.  Apparently somewhere I lost a year, or 6 months at least.  In January we will have been dating for four years...not three.One of my other friends (who shall remain anonymous to protect her sanity) is turning 30 this year.  I was under the impression that she still had another year before that happened.  She was ok with the fact that I thought that. I'm not really sure where my lost year went, but I hope it was fun!