You're comparing your insides to others outsides. It doesn't work, ever.
I stayed, for years and years. I was one of those that seemed to be happy joyous and free... And I was at times... But alcoholism is progressive, and my denial of that fact led me to accepting some very acceptable things.
We all have our own limits, boundaries, whatever...
I don't want to divorce my husband either. I HATE this whole stupid process... But it needs to be done for MY health and sanity. I HATE the thought of the kids having to go through this... But for everything I hate, I can come up with AT LEAST 3-4 things of what I'm going to LOVE about being free of the everyday life with the disease.
Maybe you should spend a little time today focusing on one or two, or more!, of the blessings that will come from your divorce. That will help you move forward.