So little bit of background. My DP and I have been together for 9 years. A few years ago we broke up and both started seeing other people. We then both decided we wanted to be together and worked through our issues and we are now happily back together. Fast forward to now and my DPs Dad is now seeing the Mum of the girl DP was seeing. AIBU to have had a minor meltdown about this?? When I say minor I mean massive! DP doesn't seem to understand why I have reacted this way. Obviously it's totally out of his control and I'm not blaming him but it would be nice if he understood or at least tried. I'm now just dreading family events etc. It's actually giving me sleepless nights, especially with Christmas around the corner. We are both happy now and it's not an issue of me worrying about DP having any kind of feelings for her it just going to be bloody awkward!