You’re not responsible for other people’s feelings, wants, desires, and needs. You do not have to meet everyone’s needs. You don’t have to do everything that someone wants you to do. You don’t have to do anything that someone wants, if it is not right for you. You’re not responsible for meeting their needs–they are. You doing something for them is just one possible way for them to meet their needs. If you say no, then it’s their responsibility to find a different way.