Take a few days off if need be to have time to breathe and problem solve without the stress of "performing" at work. I am a teacher too and I know it's hard to perform in front of the class when you're falling apart/stressed out inside.
Is there anyone you are friends with at work who might have a connection housing wise or might want a short term roommate?
I'd want to quit too and head out of town but from the outside looking in, think about how much that would hurt you long term in terms of not having good references, trouble getting another job etc... Is there anyone at work you can talk to? Most districts have something called an Employee Assistance Program- you can get the # from HR or your principal and they have resource info about everything from legal help, counseling, housing etc... Maybe look into that?
If I could do it over again, when my AH refused to go to inpatient rehab I would have said "bye, have a great life". Instead I listened to his quacking about how he was going to do it on his own. 4 months later and he's worse than ever, court involved and in danger of losing his job. And I have paid dearly on a personal emotional/health and professional level bc of how I've let this impact me.
Walk away now and don't look back. When you are tempted to return his calls/texts, post here. I wish I'd done that!