I'm so sorry for the hurt you're experiencing over this, toni. As the others said - drinking won't do a thing to help - you need a clear head to deal with what's happening. I understand - I fell back on it many times, looking for comfort & to relieve my anxiety. Just the opposite happens - we end up weakening ourselves. Better to handle this with eyes wide open rather than being numb & foggy.
I agree with what Gilmer said - let him know you'll always love him no matter what. I'm sure your parenting skills had nothing to do with his current choices. Please be kind to yourself.