Sorry you are experiencing this. It is difficult. All I can say is you'll know when you've had enough, given enough, done enough. I can also say it's better for children to grow up with one healthy parent, rather than with both parents when one is entrenched in alcoholism. Nothing is normal in that family life. Even the sober parent is spread so thin, everyone walks around on eggs... and the lack of trust just permeates everything.
Perhaps you could try a period of separation. Nothing you do will change what will be with your wife, only she can do that... but a separation can give you the breathing room you need to make better decisions for yourself and your precious children.
Above all, remember you didn't cause this, you can't cure it, and stress that to your children too as they often feel as if they are to blame for their mother's problems.