Broken family blues

Going to try to make this short. My parents divorced before I was 2, my stepdad raised me and I love him with all my heart. My real father was not around when I was growing up. 6 years ago my real father got sick with cancer and passed away with 7 months of being diagnosised. I had become close to my dad's side of the family since then and so want them to be at my wedding. My mother hates the fact that I want them there. She hates them. She also does not want my brother there either whom she has not talked to in more then 6 years either. I just want her to support me in my wedding planning and to be a mother instead of tearing me down and making me feel guilty because I want my family at my wedding. Any suggestions on how to get her to understand that?