Hi, and welcome. I'm sure this is a shock, and I will say this--If you wouldn't have married him under these circumstances, there is nothing wrong with getting out now. Staying for the sake of not wanting to admit something is very wrong can keep you trapped.
Whatever you do, practice good birth control. Everything becomes immeasurably more complicated once there are children involved, and growing up with an alcoholic parent can be devastating to children.
You don't have to decide anything this minute. But you should know that alcoholism is progressive, and this situation will inevitably become worse over time.
Virtually EVERY alcoholic lies about his/her drinking. It isn't personal, however much it may feel that way. But my guess is that he will be resistant to the idea that he has to quit drinking for good, which is the only effective solution. He may make a lot of promises to "control" his drinking, but for alcoholics that is an effort doomed to failure.
I'd suggest learning all you can about alcoholism, just so you know more about what you are dealing with, and also that you find an Al-Anon meeting. Al-Anon is for family/friends of alcoholics. It will help you to keep the focus on you so you don't make yourself crazy and you can keep a clear head so you can make good decisions about what you want for your future.