It's perfectly okay to take care of yourself; in fact, it's paramount. We alcoholics and other substance abusers are pros at making you feel like whatever is wrong is something you did. But the right thing to do, for yourself first and also for him, is to take care of YOU. Everything else is outside of your control. He is; the teenage son is; his using and drinking. But what IS in your control takes courage - "courage to change the things I can" (Serenity Prayer). You can do this.