Mother dress disappointment

I found the dress of my dreams!!! My grandma had planned on giving me some money towards my dress but now that my mom doesn’t like it and convinced my gma not to like it.. she will no longe be giving me any money to help pay for it. So now I can’t afford it myself and I’m really upset and sad!!! My mom is a toxic nightmare for reference and I’m just sad and don’t know what to do. The dress is Stevie by Made with love and I’m trying to find a used one online but still can’t afford even the used price. AHH has anyone been here? I would go work more to help pay for it but I’m dealing with a chronic pain condition which is debilitating and so I’m just in a bad spot.