I don't think you sound like that at all. Of course, I'm saying a lot of what you're saying, so I'm probably not the one to judge.
So the question is, what CAN you make of it? If you haven't had sex with your H in 2 1/2 years, how does he react to that? Mine has been nothing near that long, but H still gripes a ton. I'm not sure either of you would be content with a sexless M, though I know you have zero desire with him.
Could you give your H a half-hearted agreement, go back to your "cold comfort" and your warm fur-babies and let it play out? It is possible that he'll fail, not that I'm hoping for it. But giving up the drinking won't likely be an easy task for him. I'm just thinking you can alleviate your conscience by giving him another chance, but only one and then you're done. Though I'm not sure you even need to give him another if he's promised and failed so many times before. At this point, it really sounds like it's just a matter of logistics. I wouldn't even try to change your mental state (re-engaging) for some time, until he has proven himself.
I don't know what your H gets out of the M. It sounds like he didn't spend any time with you anyway, between work and partying. What is HE hoping for if you come back? My H wants Norman Rockwell. He doesn't live his part, but he expects me to.
I can't tell you how to get the feeling back. I don't know how.