the stretch marks are most likely because you're body is growing...taller. you don't only get them from being fat.
Just have confidence in yourself and believe that you're beautiful

Maybe try wearing it as much as you can between now and then and see how you feel?
You can still wear shorts over a one piece if you’re not comfortable or even a shirt / rashie

Don’t feel insecure, nobody will really care how you look and I’m sure you look just fine.

I too felt uncomfortable in a swimsuit, especially when we went to the pool with my class. And I wasn't the only one, so it was like supporting each other. Beauty stereotypes make us feel self-conscious. So when you're a teenager, you can be very sensitive to that and become complexed because you tell yourself you're not tall enough, not thin enough, not pretty enough compared to the others. When you think about it, it's ridiculous because we are who we are. Just because you're not tall or a size s doesn't mean you're ugly, unattractive or anything else. Not looking like everyone else is what makes you unique. You should try to say to yourself, I am the way I am, and if you don't like it, go to hell. Listen to Christina Aguilera's song Beautiful and Pink Stupid Girls. It makes you think. You have to accept yourself as you are and try to love yourself. If you really don't feel comfortable putting on a bathing suit or dressing in a way you don't feel comfortable with, why force yourself to wear something you don't want to wear. Do as you please.

i'm not sure I understand... insecure about what ? Wearing a swimsuit to go in a pool ? It sounds like the normal thing to do
It sure better than going in fully dressed or naked...

That’s not very considerate Emory

.

The end was a joke lol
But honestly I dont understand the problem ?

Simply because she feels uncomfortable, self-conscious and thinks she has to do it when she doesn't want to.When you're a girl, you understand the problem when you're in that situation.

some god advice a;ready. I think u just been thrown by what ur mum has said. try a few things, see what outfit u like. u will be with family. no-one will bother