Why is alcohol so dehydrating for some people, while not that much for others?

I tend to notice that when drinking with friends so that everyone is drinking at around the same pace, some go to pee often like every 15-30 minutes (like me) and need large glasses of water between drinks. Others never or rarely take a glass of water and might go to pee once or twice during the whole night.

It’s not about “being wise” and remembering the tip to have a glass of water, but more about an intense dehydrated feeling that you cannot ignore.

Also, I’ve noticed the same people who don’t pee or drink water between drinks, really don’t get as bad hangovers and they might or might not take a glass of water in the morning to feel “OK again”, whereas I would need litres and litres of water for hours (maybe the whole day after heavy drinking) to feel rehydrated again.

What causes this difference?