Jennifer,
About a year ago, my husband went into treatment when our baby was just 2 months old. It has been a hard time since treatment because he has relapsed 4 times. I can only imagine what you are going through with everything plus the sleep deprivation and the fatigue of being a new mother. Al Anon helps so much but most importantly try to become selfish and take care of yourself and your baby and put him on the back burner...I know that's easier said then done since I'm the worst at my own advice. I just know if I did that I would be happier so maybe it will work a little for you.
Reach out anytime,
Megs