Six years. I've heard that it's not necessarily effective to be with one T for too long, but because of my history with frequent moves and frequently terminating relationships after a few years (because I had to), it's taken this long for me to get attached enough for me to be irritated :-/

Up until this year, I would have been fine just to stop seeing him and been like, "Whelp, that's life..." and then through this last year I realized I would be very sad to leave him and it's been a very, very, very long time since I've felt that since I learned not to attach myself