This post has got me thinking all day, and even as I type I am not sure of my conclusion.
Part of me thinks that he realizes every single day what he has lost and is losing and it is palpable, like a cape tight around his shoulders. When I am successfully detaching, it is just there and doesn't affect me. On bad days I feel angry he's having this pity party and doing nothing about it, or sad that he his so unhappy and unwilling to take the steps to change. On the worse days, I figure it's an act to elicit sympathy.
Other thoughts are that if I leave him, I will suffer a real loss of standard of living (not that plush now) and he will benefit. I am unemployed (2 years) and if I get work, I can probably consider myself lucky to make a third of what he does. Any money or the value of the house that we split is a result of my inheritances and/or scrounging and saving I did while he spent every cent he had at his disposable (I set up separate accounts for this years ago). So that really tempers the "will he know what he lost" question, and truthfully burns me.
I do know that no matter what happens, I am so glad that I am not an active addict of alcohol or any other substance. It's bad enough on the sidelines, I wouldn't want to be facing this battle myself. I guess with that thought, on my good days, I'm ok if I don't know for sure if he realizes what he's lost / is losing.
I'm pretty sure I'm gonna be thinking about this for a while yet though. Good thread!