I agree totally with all that Laurie shared.
I'll just add that just because I have not set a clear boundary...it does not free the other person to do anything else I may find in the future to be unacceptable.
I have always hold the right to change my mind if I decide that my boundary was not specific enough to include some things and addict might do. The only reason for me to even have to state what _my_ specific boundaries is really a just a warning, not an excuse to tip-toe up to a line that I have set.
The reason I share this perspective is that so many times when in the moment, I was not able to enforce because some situations could be vague or even unprovable..."I didn't leave that here...my friend did." "You said if I didn't steal from you that I could stay" etc etc.
Non-inclusive detailed conditions just wore me out and the day I realized I could just say "stop" and/or "no more" and mean it....that was enough. Just some food for thought.