I was late to a friends birthday party and when I arrived most of my friends were well into their third glasses of wine. So when they saw me they teased me about being fashionably late and that I would probably be late to my own wedding. I said it wouldnt be for a while and they ended up telling me that my boyfriend came to them and told them he is proposing on july 4th. I know I should have told them that I didnt want to know any more details but I couldnt help myself and now I know how exactly how he is going to propose. I am feeling guilty because I know how much thought and effort he has made to make this moment special and I think he would be pretty upset to know that my friends spilled the beans. Should I tell him I know so that he has time to change it or should I just go with it and hope that I can fake being surprised?