I can only speak about myself. I personally would most certainly go to wedding shower if my husbands friend was getting married and I was invited. Even if bride to be is not my favorite I’d still go. The only reason I’d not go to is if I have true reason like was feeling sick or was busy with something important like job conference etc Not knowing other people would not stop me from going to events. So I am no help here. But if you decide not go just say you have a bad cold or something, not feeling well is a typical reason not to attend something .