I got so lucky with my xh seems a weird thing to say, but having read extensively on this topic I discovered that there is a "vulnerable" type of narc. To some degree he still cares a lot what other people think (like his friends etc). Plus, because of all my research I've been able to exploit this to make things reasonably manageable. It sounds horrible but it's really the only way I've been able to have some sort of stability in mine and DS's lives.
What gives me anxiety is the future really and not knowing how things will change as DS gets older, and knowing I'll be dealing with him for the next 14 years at least. For now things are easy because he still has to impress his pregnant gf but I suspect it's only a matter of time before things go south.
Reading through this, and the mention of vulnerable type lead me down a rabbit hole because OMG that's STXH. Eye-opening and terrifying for how this D is going to go.