A bit paranoid about partner going to work Christmas party..

So my fiancé is going to his work Christmas party tomorrow night and I don’t know why but I’m feeling anxious about it .

I’ve found that every time he gets drunk he gets quite flirty with girls and me not being there I’m scared he’s going to get flirty with them. At the same time I don’t want to be a psycho gf so I just said to have fun and to try not to get flirty with girls and left it at that.

How am I going to get through tomorrow night without thinking the worse , it sucks.

It’s also more so that I don’t trust the girls that he works with

Update : thanks for all the concerns regarding Covid but we are in Australia and in my town we have no restrictions, they’ve all been lifted due to little to no Covid cases :)