I have lost all of my confidence

Just a little background info... I am 12. I am a little tall for my age. I am also stronger than most girls. I had the worst self confidence ever because of comments complete strangers make or what my “friend” tells me. My “friend” is just a bitch to me. I worked so hard for about a week to get my confidence up. It only lasted for that week. That is what I came here to say.

Btw.. y’all shouldn’t start commenting on my age. I have a period and know what sex is. I’m very educated.

So my confidence only lasted about a week. My grandma took me shopping today. We got 4 shirts and 3 shorts. I came home and showed my mom the fit. (I have a bigger thighs and a bigger ass than the other girls in my grade). I have a sprained foot but I went shopping for 2 hours. That is how bad I needed new shorts. My old shorts are way too tight. So... I put on the shorts to show my mom. Two of the shorts are size 14 from justice. The other pair is a size 0 from the adult section in target. The first thing I showed my mom was a pair from justice. (I’m not a girly girl but they have good jeans). My mom said there is a dent where my butt crack is. She said that but she is sitting there in leggings which really shows where your butt crack is. Plus, I don’t see a problem with a little dent where your butt crack is. It isn’t like I’m wearing clothes as tight as her. She said that they will shrink in the wash and get too small. Then, I showed her the pair from target because both of the pairs from justice fit the same. I was hoping that I could at least get one new pair of shorts. She said that they are too tight in the waist because I don’t have a whole lot of room to grow and they will shrink in the wash. She said that I have to go back to the stores and get bigger sizes. I told her that I tried on the bigger sizes (yes, I did. I didn’t lie). I told her how they fit. They were sliding down my legs from being so big. She said that they will shrink. I tried telling her how big they are. She won’t listen. My dad didn’t say anything because my mom does the clothes shopping. The next size up at justice is a 16. That is the last size before plus sizes. I don’t want to be wearing plus sizes. At target, the next size up is a two. Size two makes me feel fat and ugly. They are so baggy in the wrong places. I HATE baggy jean shorts. She knows that. I feel so fat knowing that my mom is making me go a size bigger than what is comfortable. She told me to go shower. I started crying in the shower because I feel so fat. I was also crying because a week of building up self confidence just went down the drain. I only have 2 people to support me. One is my best friend and the other is my cousin who is 20 and I barely get to see. My parents will just make me get the size bigger and my grandparents on my dads side will just agree with her. I rarely see my grandparents on my moms side. I rarely see anybody on my moms side of the family. I get to se my dads side more often but they wouldnt really be able to do anything. My cousin that has always had my back is in college. I rarely get to see him. My bro and sis are younger than me and wouldn’t be able to do anything about it. I feel like the only person that I can talk to is my bff. My parents have always had my back but not with this. I will get in a lot of trouble if I try to argue against them with this even though I know what is comfortable for me.

Btw, the lady at justice said that a size 12 won’t fit because I have a big butt. She said that to my face. I wanted to slap her. I am so mad. I wish people wouldn’t make comments like that. I have had so many little comments and I have been cyber bullied too.

Sorry this is so long. I am just trying to get some advice.