My boyfriend and I have just hit the two year mark. We’re basically best friends, very much in love, have brilliant s**, all that malarkey but…

I’ve been with someone else in the past for just over two years, and it was around this point that things started going wrong. I know my new boyfriend is a totally (TOTALLY) different person to my ex, but I’m worried it might happen again.

Am I being stupid? Or am I right to be concerned?