Form of enabling: Safety
When living/spending time with someone who is not an addict, period... there is a sense of safety because even though the addict is in denial - they do still "feel" that sense of protection. Now, it's when the codie lays a boundary and then doesn't go through with it - that the disease is given a license to progress, for they still have their "protection/safety net" in place.
I can think of many times that I have been "not - sober" and have felt SO much safer knowing there was at least a sober person around for crisis/emergencies and that they would handle them. It wasn't that I was taking that person for granted - after all - it's their choice to be the "DD" or sober person or someone who has sobriety, and boy I sure am grateful.
I know that if I were living a life on being high and around people who were constantly high (didn't have my "safe house" or relationships with sane people) - it would feel 'unsafe' and hitting bottom would come a lot quicker than if I was given a soft place to land.
Look at the relationships your guy has - what do you think he gets out of all these relationships? Do you see enabling in any of them?