On the wall of (shame)
Relating to his previous dependency issues, he admits that being an alcoholic and having other drug problems was a shameful thing to be considering his commitment to his family.
Also, some bars used to (maybe still do?) have a “Wall of shame” where they would put pictures of patrons, often in embarassing poses, notorious for getting wasted in the establishment. Like this one here:
Because of his fondness of alcohol Em would probably end up on a wall like this for sitting in bars and getting wasted all the time.
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