What is the fallacy when someone accusses another less of what they themselves do.

I would say that this primarily a strawman fallacy . Person 1 is saying that person 2 is an "alcoholic" and person 2 is substituting a person’s actual position or argument with a distorted, exaggerated, or misrepresented version of the position of the argument. by implying that the argument is actually against drinking alcohol. The fallacy isn't with accusing someone of doing less then what they've done, but in misrepresenting the argument being made.

First, let’s get the definition of an alcoholic as the word is used in common parlance: it is anyone who drinks more than I do. 

In addition to the other errors noted, I nominate Tu quoque (“you too”) is an appeal to hypocrisy. The argument states that a specific position is false or wrong and/or should be disregarded because its proponent fails to act consistently following that position.

Of course, the Fallacy of Diversion comes in (when you divert the discussion to something more comfortable when you have no answer to the topic at hand) because one wants to divert the focus to the other person’s drinking.

Let’s not forget the Appeal to Righteous Indignation in defense of drinking. A person claims to be offended, insulted, or hurt by criticism of a proposition he holds, or the advancement of a proposition with which he disagrees. Intrinsic to this fallacy is the principle that attacks upon an idea are morally equivalent (verbal or physical) to attacks on a person, and an attack on an idea justifies a response equal to or greater than the initial “attack.”

And, since “you drink too much,” the Fallacy of the Argument from Intimidation (appeals to moral self-doubt and reliance on the victim’s fear, guilt, or ignorance. It is used as an ultimatum demanding that the victim renounce a given idea without discussion, personally attacking by threatening the victim of being considered morally unworthy, uneducated or just plain stupid. An ad hominem attack.) may be appropriate here.

I’d love to add more, but my beer salsa is dissolving the insect paddies and synthetic ham is soaking my egg substitute breakfast.

As Bo says it may be more a strawman fallacy but it might also be considered an example of false equivalence.

The basic idea behind a false equivalence is captured by the common phrase “you can’t compare apples to oranges.”

Logical Form of False Equivalences
Here is the standard logical form of a false equivalence fallacy.

A and B share properties a, b, and, c
Therefore, A and B also share properties d, e, or, f.

So you share the property of drinking alcohol but you don't share the property of drinking alcohol excessively.