Advise on bridesmaids

I asked 2/3 sisters of the groom side to be my bridesmaid. My fiancé has backed me up and says if she doesn’t like it tough. The reason I never chose the other sister was because in the 8 years she never makes me feel like family I think twice she ha came out for my birthday. Oh and the fact we got engaged the next day her “partner” got her a wedding ring and she had to tell everyone one.... One of the sisters I chose said she is happy to be chosen however feels like the other sister won’t feel part of the wedding. Am I in the wrong for not making someone my bridesmaid... I feel like planning this is showing everyone’s true colours? Any advise is much appreciated xx