I saw what drinking did to my Grandfather, it killed him. He threatened to kill my father and grandmother an uncountable amount of times. He chased them out of the house with a chainsaw, he threw his life away for alcohol. He was a great man, but one night his co workers where drinking beer and he thought they would think he wasn't cool if he didn't too. That was the start of the end. He had a heart attack. I saw my other Grandfather kill himself from smoking, he died from lung cancer. Both of them I hardly knew, I could have known them better if they didn't make such foolish choices. Drinking and smoking is something that harms your body and mind in so many ways I don't see why anyone would do it. I know because I'm young it seems that I don't know anything and can't make real decisions but that's all wrong. I have decided I won't hurt my family the way my Grandfathers did. People pay hundreds just to quit drinking or smoking. It's better just to never start in the first place. It makes your life so much shorter and can ruin those around you. I think I'll stick with water.
Alcohol doesn't affect everyone that way, but I'm sorry that happened to your family. I'm certainly not trying to convince you to drink (in any way, shape, or form). I'm just saying that not everyone uses alcohol that way, and you shouldn't judge people so quickly for casual alcohol use...when used appropriately it's not harmful to most people. Some people are affected in extreme ways by alcohol, and I know some of those people (and they've learned to stay away from it), but it doesn't affect everyone that way.
If you've decided not to touch the stuff then good for you, I would just encourage you to keep an open mind about others, though, because it's something that's quite normal and harmless for those that don't have problems with it.