Swim Suit problems

So lets start by saying I have thick thighs, always have and always will (at 100 lbs my thighs were still thick). My husband and I have this vacation plan where we will doing a lot of hiking followed by swimming and having to hike back, and a waterpark with swimming and a bunch of walking mixed in. Well my swim shorts go to about mid thigh and last year I left the water park with my thighs being raw. Well do they make swim shorts for woment that go mid thigh? Would it be better to buy mens swimming trunks? Would it be acceptable to buy knee length work out shorts and wear those instead of a bathing suit or would the wet cotton cause a similar problem (not to mention being a little heavier)? I don't know what to do, I asked my mom and it just brought up a rude comment about my weight.