Part of my diagnosis is a personality disorder unspecified involving narcissism. Can it change? Supposedly but I've been told it'd involve a few years of good therapy. It may be more malignant narcissism, but still narcisstic personality either way. I have other disorders aside from this (i.e. schizophrenia) and am not 48 years old. A person cannot change merely by the snap of the fingers, it takes time. For the therapy to work, you need dedication and full co-operation. I couldn't care less about changing my personality and such but do want to change the things like schizophrenia so it is necessary to be dedicated.

Whether he has done this or not, I'm not sure so maybe you could give some enlightment. Has he ever had "narcisstic rage"? This doesn't necessarily need to be physical, it can be emotional or verbal.

So, can a person change? Yes. Will they change? Depends on things like commitment and if they even want to change in the first place.

One of the things narcissists are usually good at, as well as other personality disorder sufferers, is manipulation. He may say he'd go for the treatment but you'd need to watch out. Think of it this way:

Suppose you're any type of animal (humans are, so it works but whatever) and there's another animal (him). If you are stronger than he is, he's probably not going to try to attack you. However, if he senses or sees a weakness, then he may. He could also create one.

By the above lines, I don't mean that he's going to attack you but the attack was more of an analogy to manipulation. If there's a weakness, it'll be exposed and used, probably not right away. So, let's say he goes into therapy and you eventually cut him slack, he could try to act more and more dedicated to get more slack and use that slack against you.