I agree that if your friends dont accept you than they were never really your friends. Your family on the other hand isnt something you could write off like you could friends. If you really think they would respond badly, and you want to maintain a relationship with them, than maybe you shouldnt tell them at this point in time. This may not be the answer youre looking for, because hiding something that is apart of you that you finally feel good about is never what someone wants to do. It really comes down to how homophobic your family is, and how much of a relationship you want with them. If you feel like your parents are more open to it maybe you could tell them but not your sister and her family. Good luck.