Removing bridesmaids/couples shower??

Hi there! I’m in desperate need of some advice. So my wedding is next month (yay!). Like most, planning my wedding wasn’t a walk in the park.
I have two problems.

First, my 3 bridesmaids. My MOH is my step sister. Now, I’ve always felt like I had to make her my MOH due to my dad and step mother. I know my step mother would throw a huge fit if her daughter wasn’t my MOH. But I completely regret it. Although my step sister and I have never had any trouble with one another, we never talk either. Honestly, I know she really couldn’t care less about being a part of my wedding. She never once called me or text me to congratulate us on our engagement or offered to help me with my wedding details. I never really expected her to help me out but I at least thought she would tell me how happy she was for me! My 2nd bridesmaid, my sister in law, has been the complete opposite (not in a good way). She’s very controlling and has demanded months and months ago (at the beginning of our engagement) that the dress I pick needs to look good on her body type. She also demanded that all the bridesmaids have the exact same colored nails as her on my big day AND she demands everyone uses the same hair and makeup stylist she is using, AND she demands that my fiancé and I invite two of her best friends to our wedding. It’s outrageous!! My 3rd bridesmaid just text me last Friday about where to get herself sized because she hasn't ordered the dress yet!! My wedding is in the beginning of October and she hasn’t ordered it yet!? I told these ladies many months ago to order it no later than July!!
I’m thinking about removing all three of them. They have in no way helped me out or honestly cared too much that it’s my wedding.
I think I’ve screwed myself over with trying to please everyone and not actually listening to what I want.
second problem, my step mother wants to throw my fiancé and I a couples shower. The problem is, she wants to invite everyone on her side of the family. But these people are not invited to my wedding . As soon as she finds that out, she’s going to be very ticked off! Honestly, although it’s sweet of her to want to throw a shower for us, I really rather decline her offer . I think it’ll be way too awkward (no one on her side of the family even knows my fiancé’s name!). Also, I wouldn’t want people who are not invited to buy me and my fiancé wedding presents, it’s not right. Side note: neither my father nor my stepmother has helped out in anyway with my wedding expenses. I’m in my early twenties, so I would’ve thought my dad would at least help with my wedding dress expenses or some of the catering! Instead my future father in law has paid for everything for us. It’s so embarrassing on my part. Especially since my stepmother makes $$$!
So please, any advice on how to handle my bridesmaids and the couple shower would be much appreciated. Tysm!