How can i avoid wearing bikinis? people expect me to look good in them?

i look good in clothes and shorts so my friends expect me to look great in a bikini which i dont! i have nice hips but a flat square butt and my upper thighs are flabby.. people cant see this in shorts but in a bikini ya im terrified i always have to wear modest swimsuits and people think its weird that im insecure but i want to keep up this fantasy that i have a perfect body and in a bikini thats all gone lol