I've been reading Rick Atkinson's An Army at Dawn, and there is frequent mention of Churchill's drinking. He also writes about certain military generals being looked down upon and reprimanded by superiors because of alcohol abuse, but (as of yet) there's no mention of others' opinions of Churchill's drinking.
One book I've recently read about Churchill states that his energy was tedious to those around him. He would keep a light buzz, if anything, and keep everyone up into the late hours of the night going over policy. He even strained the patience of career military men. I had always figured he would be a fun guy to be around until I read that. Here's the book.