Someone from the outside to look in please?

From an outsiders perspective, you were wrong. Because you and your family were at odds, you invited her to be a bridesmaid. By definition, you were willing to use her for your purposes, even though you neither wanted her there or liked her period. You wanting to use her because you had no one else, apparently not having the wedding you planned wasn't an option seeing as how you could've not had as many or any bridesmaids, the same way you're saying she wanted to use you to get her a dress and some shoes. To top that off, once you and your family resumed pleasant relations, you want to ax her being your bridesmaid. Beyond that, you did it in a cowardly way by using problems in her relationship as a reason for not wanting her as a bridemaid. She didn't offer to step down, you implied that she should. You did her dirty because as you said, it was YOUR day and I guess that means that no one else matters but you. You say you hate two faced people and have lost respect for you but you're the one being two faced and unseemingly deserving of respect. Going against the person you are and the beliefs you have must mean stepping over someone else's feelings for your own agenda because that's exactly what you did. However, she was completely out of line for trying to cause problems with you and your husband and you should tell her so. You should admit that you were willing to use her because you had no one else at the time and you should confront her about only wanting to be your bridesmaid to get a dress and some shoes, and give her a chance to address your concern. I doubt it would fix your problem but if you're starting from ground zero, you're at least giving her a chance for the sake of your husband's friend.