Yep... alcohol is a GABA antagonist, so the brain starts making more and more GABA to compensate, so you can function and not go into a coma from the booze. When you take away the alcohol the excess GABA hits your system and can cause anxiety, seizures, and sleep disturbances.

Alcohol also suppresses REM sleep, so your body during recovery shifts to almost 100% REM sleep (see Harvard psychiatrist Allan Hobson's textbooks for more on this, "The Chemistry of Conscious States" is great). That in combination with high GABA concentrations means people can experience hallucinations and sleep disturbances -- this mostly affects heavy constant drinkers.

Doctors will usually prescribe a sedative for recovery, usually a benzodiazepine, which suppresses GABA like alcohol does. However baclofen, a muscle relaxant, is especially useful for alcohol recovery; it's a GABA antagonist also and weakens the cravings substantially, I have lots of good things to say about it. Naltrexone is another drug that does the same thing via a different mechanism, as an opioid antagonist, but I don't really know anything about it.