If it's a problem for you and he's hiding it, it's a problem.
My husband never looked drunk, never staggered, did not fit the 'typical' picture of an alcoholic. Nevertheless, I learned that he is. It was a problem for me, and he was hiding it very well.
Educating yourself will help you sort things out in your head. Read the stickies at the top of this forum. Two good books are "Under The Influence" by James Milan and "Codependent No More" by Beatty. You can get them at the library. Also look at attending an Al Anon meeting. Once I got more info about alcoholism, I could see how typical my own husband's patterns were. Good luck, and keep posting! Reading here on SR has been such a help for me. I came here feeling so alone and then realized that my story is typical. My experience is very similar to yours --- it all just sneaks up on you, and you feel like you might be going crazy! You are not. Hang in there!