Naw, you aren't an idiot. You just let your codie self take over the real you. So shove that codie self way down inside for tomorrow and act as you know you want to. If the codie voice pipes up about having compassion for him, tell the codie you have exercising compassion for yourself and for him by kicking him out again, that you deserve to have a home without the stench associated with him when he is drunk and that he deserves to be treated like an adult.
And once he's gone again ('cause I know you can do this) its time to start some serious work on yourself to figure out why that codie you comes back so strong at the first sign he needs to be rescued from himself. Concentrate on you and your own issues. Life will get better for you.