first of all... you have to follow the whole convo not just dissect one sentence...
If you read the whole thing, I was stating how that (again, in my opinion) that if the addict is not actively recovering after a long time while living with the loved one, that they may be not helping the addict but rather enabling them in some ways...

...but to better answer your question, I would say that some of those ways would be as follows:

if you live with someone for a long time while they are actively using, you enable them emotionally by the fact they feel they won't lose you know matter how long their drug use... this can destroy the addict in my opinion as the longer they use the less likely I believe they will ever come to the point where they really are serious about quitting drug use.

Then there is the fact that you are giving the addict a long term sense of stability... again that can be devastating the longer their drug use.

Then their is always some sort of financial support in some way, no matter how small or insignificant you think it may be, which is very, very bad for a meth addict.

thats a few off the top of my head..