I have been married for one month. can I file for divorce or do I have to wait? is anullment an option??

I found out mid June my fiance was an alcoholic. I informed him that if he doesn't get help and stop the wedding would be cancelled. He agreed. We got married July 18th 2014 . After we got married he began drinking again. He's been on 3 binders lasting a minimum of 2 days or longer and been drunk days in between. I drew the line when he decided to get drunk while watching my son from a previous relationship. Who is 4 yrs old. After a few days of not speaking he decided to pack his things and leave without saying a word,while I went to my 26week checkup.(I am pregnant) we spoke and he says he's confused he feels he made a mistake by marrying me, he needs time. Hes been calling me while he's drunk saying he scared I'm going yo leave him because if the drinking but won't stop drinking or get help and doesn't plan on ever getting help. Some ppl have intervened but no results. He's been drinking since Aug 10 left Aug 14 and been drunk for 4 days. I'm at my wits end