According to an article, the two ailments seem to consistently feed one another. If a person is an alcoholic then there's a good chance they are suffering from depression as well.
The accelerated problem of having to deal with both conditions is that it also increases the likelihood of a person attempting suicide. When a person is depressed they have an altered state of mind to begin with, then add alcohol on top of that and the problem only increases.
People may do things when they're depressed that they wouldn't do otherwise. Alcohol has the same effects.
When an alcoholic seeks help or decides to quit drinking on his or her own, that is a great first step, but it can also be a very dangerous place for someone who is depressed. When the mood altering drug is removed, the first few days of withdrawal can really wreak havoc on the addict's mental state.
If alcohol had been used as the crutch for some time for a person who finds relief at the bottom of a bottle or glass and then is removed from the equation, until the alcoholic figures out how they feel without drinking in their lives it could be quite concerning for the person's family or friends.
Strong support systems are so important to those who are dealing with coming off whatever it is that they depend on. If one has a tendency for depression or their illness is increased when they have been using another substance to fill a void, then they must be under the watchful eye of a medical professional or loved one.