I'm so sorry of this turn of events, but considering how reluctant he was when he left, i'm not surprised. Having to give up his booze and face his demons didn't seem to sit well with him.
What can you do short term?
a) a weekly hotel rental until you can find a sublet
b) look on Craigslist for shared accomodations, perhaps with another mama, seeing you'll be bringing your child with you.
c) POST on Craigslist yourself to find something
d) if you feel comfortable, perhaps discreetly discuss your situation with your superior so he or she knows how precarious things are right now.
e) take some time for yourself...perhaps arrange for a night out someplace, go to an Al-Anon meeting...Now more than ever, when you're trying to extricate yourself from a difficult situation, it's a good idea to remember the HALT rules (Hungry, Angry, Lonely, Tired).
Keep posting XXXXXXX. We`re here for you.