wedding event

My Sim and another random Sim are trying to get married, and I have tried planning the wedding event. I did the whole "select guests" and chef thing and also chose a venue I wanted the wedding to be at, but suddenly my game is stuck on the loading screen with the green crystal and won't load. I had to restart my computer 3 times, and it is still doing the same thing. I decided to try again and host the wedding at my house, but after I started it, no wedding happened, and my Sim went to bed. This has never happened to my game before.