Twenty-five years is a long time. Of course you're experiencing some pain and loss. Now that you've been apart from him for six months, you're seeing how his narcissism has damaged both you and your kids. You're seeing how manipulative he is. You believe that he's an alcoholic, but he hasn't drank since you left months ago.
The first thing that comes to mind is the term "dry drunk" from AA. I'm not very knowledgeable about this, but from what I remember hearing, alcoholics manifest similar behaviors even if they're not actively using. You might Google this and learn more about the topic. I'm sure there are many articles written about it.
You ask how do I let go. It's a challenge to move through the stages of grief in letting go of a relationship. Keep on posting here and you might also post on the Detaching from a Failed Relationship board.
https://bpdfamily.com/message_board/index.php?PHPSESSID=a29329f3a5f4829b6eafa53ad79ae179&board=8.0You'll find lots of company there. So sorry for your heartache. It gets better.
Cat
