Self conscious

So I have stretch marks on my hips, inner thighs and my butt and tiny bit on my boobs. I've had the inner thigh stretch marks since I was 10-11 (started puberty / was chubby for my size) and they have gotten worse to this day. I'm young and so self conscious by them, to me they look so gross. I can't even go swimming in bikinis because of how it makes me feel and having ppl look at them. And even when with my ex I couldn't not try and hide it. Does anyone have any suggestions on how to improve my confidence with this?