I would just say No. It is very hard for me to say and I have been another person who has tried to make the offending person not feel uncomfortable. By doing that I have had bad feelings about myself that are hard to get over. So I am learning to just say No. The more we practice it when we know it is the right thing to say, the better we will get at it. So just say No. She knows she is in the wrong, but wants to make it ok by having you agree with her. Don't!