If you wish him to be clean and sober - perhaps it will help to recognize your addiction to the drama and adrenalin that comes with being codependent and sharing life with an addict - it's also your turn to 'get clean' - stay away. Life by example - you can do it. Kick the habit !!
We've been there and there is no easy way. You and your child are better off without him - you can write your own ending
I know how difficult the feelings are - speaking from experience but you already have experience that shows how this will work out again and again and again. Go cold turkey and no contact. Save your evidence in the event that he claims down the road that you kept your child away from him.
Best wishes, strength and hugs
Joie