How would you comfort / advise your son?

My 17-year old son asked a girl he liked very much to the prom a couple months ago and she said, “Yes.” They weren’t dating, but this young lady led my son to believe that she really liked him, but wasn’t ready to date him yet. She was however, estatic to go to the prom with him and even texted him the times she went to look at dresses.

Well, my son just found out that his prom date is in a relationship…with a girl. Apparently she has been for a while, but still wanted my son to take her to the prom. He is hurt and confused. He doesn’t want to take her to the prom, not because she is in a lesbian relationship, but because she lied to him and led him on. He is afraid of what people think AND is feeling majorly rejected. What advice would you give your son or insight do you have?