"I'm Codependent" says a lot. The alcoholic seeks out (subconscious) the codependent for relationship the same way a bug is drawn to a light and vice-versa. They feed off each other and in a most unhealthy way fill each others "needs".
One problem is that alcoholism is progressive. The chronic long term ingestion of booze affects the brain chemistry of the A as well as causes physical deterioration to the body. Anyone who has lived with an A has suffered emotional & verbal abuse. You are not alone.
Another problem is that we develop habits as we go. The habit of snippy remarks or a sarcastic attitude takes a back seat to the emphasis everyone places on "detox" for the substance abuser. Even the spouse (who's constant subjection to addiction) is affected and their thinking also becomes distorted. The Spouse not seeing the "progression" ( or better term the degeneration) of the alcoholic because it is slow and builds like dripping water believes if the substance is removed..all will be well.
Patterns have been established on BOTH sides. The good news is they can be broken and new habits established. The first thing for the enabler (co-dependent) is to Detach and realize that they did not Cause, can not Control nor Cure the addictions of another. When you realize this the "people pleasing" can stop and boundaries can be set.
Boundaries are a reflection of our self-respect and lack of them invites disrespect. Slowly the co-dependent must learn to keep the focus on them (and not pleasing the spouse, facing the fear of abandonment {a co-dependent's worst fear is the loss of the relationship..no matter how toxic} will diminish as confidence and self-esteem increases.
One way to do this is to find your voice. Say what you mean, mean what you say and try not to say it mean. Most importantly IF you do not mean it, do not say it. Boundaries are not rules for the A to go by, but actions we will take in a certain situation should our boundaries be crossed. Will the A test your boundaries? COUNT ON IT. But if we have detached we do not have to take this personally (QTIP). We learn to act rather than re-act. There need not be a grand announcement regarding boundaries but short statements that are to the point.
Examples:
"We can continue this conversation, when you are willing to discuss it without sarcasm"
"Sarcasm is not a joke, and this conversation ends until you are ready to continue without using it"
"I will not respond or honor a request made if you ____(curse, yell, what have you) at me." "I must insist for this conversation to continue, that you use your indoor voice"
"If you are late and do extend me the courtesy of a phone call, I will not wait for you and continue with my plans"
Give thought to Whatever unacceptable behavior you wish to address, and allow time for progress before throwing down the gauntlet
Boundaries can prove to be inconvenient at first. You will have to plan in advance (you know when situations will likely occur) to remove yourself (leave the room--I took so many showers the first month) or keep busy (I also painted my nails a lot and kept a lot of salad handy so I could eat conveniently) with a list of short tasks that will divert you from "caving in" or being "hovered" (manipulated and sucked in) to changing or accepting "blame". Remember when you remove the "m e" from blame all you get is Bla Bla Bla.
I am so glad that you are willing to move from survival (victim) to recovery.
PS That is the Title to a great Al-Anon book that is well worth the read.