Should I be so upset

Been divorced for less than 1 year, separated for two, the one year anniversary is at the end of this month. I just found out that my ex-husband took his girlfriend to St. Croix. This was the island that we visited most often as a couple and I thought was our place. We loved this island and have amazing memories here. They posted pictures at my favorite beach. Should I be upset? Should I feel that nothing we had is sacred, or just ours, or just mine? I'm heartbroken. I can't stop thinking about it.