Relapse is definitely part of the recovery process, and a huge learning experience but understand there has to be some recovery that took place to use that word….a few weeks, months not using, still very much in behaviors that show active addiction without taking the drug is different than time in where the changes are becoming obvious, blame has faded away, personal responsibility steps in, others feelings are taken in consideration, work is being done to make amends, clean up the wreckage … You can see the difference.
Other than that it can be an excuse, just like the saying progress not perfection can be used as an excuse just to justify one’s own bad behavior.
Your boundaries are about you. What you will not tolerate, what you can’t live within, places you won’t be going, lines you know aren’t healthy for you to cross…
And you don’t need to talk about them to him, just make them and stick to them. This is your recovery now, his is different. Work your side!