Here's the deal April ..... as alcoholics, that's how we "cope" with evertyhing. I didn't know any other way. The fact of the matter was I was not coping. Not even a little bit. I was living in this fantasy world that told me "If you had this tough job and depression and stress, you would drink too. I deserve these drinks."
REALITY: I was miserable and I was slowly killing myself.
No one said quitting drinking would be easy but it IS possible. May be instead of looking at the next five months and convincing yourself you can't get through it, you should consider taking it a day at a time, or a second at a time.
Also, consider talking with your boss/manager about getting some extra help during your co-workers maternity leave. In my opinion it's better to say upfront that you'll need some help than to let your work suffer.