Reducing puffiness? Help?!

I drink a lot of water. And by a lot, I mean A LOT, like 10-14 glasses per day at least. I have constantly been drinking a lot of water since young and I feel like over the recent years, I notice myself getting puffier. And I have jiggly arms and stomach that ripples when I have rigorous movements, it’s disgusting. It feels like a big percentage of my body is made of water/fat. Have you ever encountered such issue? How did you resolve it? For the record, I have PCOS so my doctor says it’s one of the reasons but I’d like to be slimmer again and most work-outs/diets do not prove to be effective and every time I see my slim friends eating a lot while I’m stuck with a tiny portion, I hate myself so much!