Yes, it is very much their life not mine, and that's fine until it has a negative impact on hubby and therefore on me (or directly on me, which I am trying to stop).

(Stepson is profoundly self-centered -- is that a type of narcissism? lol)

Trying to not enable him is the very tip of the sword, or the most crucial bone of contention. Hubby just cannot (99% of the time) step up and say "no" to Sonny...