I'm sorry to say that if your husband is truly addicted to the Vicodin (and it sounds like he is), the "couple of days" to ween off the drug is just another excuse and will likely not be the end of this nightmare. At this point, I would suggest reading as much as you can on this forum and asking as many questions as possible. Also, have you tried going to an Al-Anon meeting? I think that might be very beneficial for you - It certainly has helped me tremendously with my alcoholic husband.
I'm sorry you are going through this.