I began drinking when my kids were in their teens and it's by far, the biggest regret of my life. I wasn't there.
You said you don't remember which chapter or which book you're reading. Are those the memories you want to have of your children growing up? It's okay to be agitated and impatient sometimes, as a parent. It's hard to be relaxed and enthused all the time when you have small children around, but drinking and taking drugs is not the answer. There are lots of parent support groups online, and probably in your community where you can share your feelings and ideas with others moms.