My fiance's sister is my maid of honor and she said we should invite their mother when we look for dresses. Fine with that, but they also have a step-mom who has been in my fiance's life since he was 3 (& married his father when he was 5) so she very much considers herself the 3rd parent. I wasn't really forward to having her involved. She prides herself on being a "feminist" and thinks that means being as masculine as possible. No dresses, heels, or make-up for her! She is also difficult to shop with because she has very different taste than me & gets upset when you don't "listen to her input". Also, there's having the mom and the step in the same room, never fun. My future sister-in-law was going to discuss it with her dad and see if she cares either way (that way we dont hurt her feelings by not inviting her, but she would be pressure into coming if we invited her & she didn't care). However, she has not called to congratulate us on our engagement. She was out of town when we told his father but no word from her. This is odd to me because they seemed eager for us to get engaged. Should I potentially upset her and not invite her or be the bigger person and ask her to come?