NPD is a diagnosis that sprang to mind when reading the post and a personality disorder does seem to fit the described presentation best.
I agree that people with symptoms of these disorders are less inclined to seek treatment.
My impression is that you may be contributing to the difficulties. In your profile you mention that you are a 'doc' which I am assuming to mean a doctor of medicine. You also say that your husband has Bipolar I disorder. I believe that you should leave diagnosis to a specialist and approach the issue as a concerned spouse.
In your journal entry you also allude to the possibility of leaving. If you are unhappy in the relationship, and it is abusive, then you should leave. You could also set limits on the relationship, if it is safe to do so, and make his treatment a condition.
You mention an arranged marriage which I assume to be in India. I have been abused by an Indian male doctor so I carry significant prejudices against this particular culture.
I have experienced Indian males to be extremely controlling and aggressive in their approach, especially when confronted by a female.
Your husband may be more approachable if he were to limit his drug and alcohol usage. These can be used as defense mechanisms so it stands to reason that he may have underlying emotional issues.
There is an abuse support community forum which may be able to offer additional advise.
Another option may be to consider respite. Perhaps a period away from him with friends and family. They may be good people to go to for support too.
Needless to say there is no way of doing a diagnosis by email... however I would be inclined to consider what are called the "dramatic" personality disorders (antisocial or narcissistic seem like possibilities). This is mostly because what you seem to be describing is a fixed pattern of behavior... whereas with a mood disorder you would expect "cycles".
I am not as confident that a psychiatric evaluation of your husband would help right now... you haven't suggested that he feels he has a problem.
I am more concerned about you. You are going to need lots of support. I wonder if any of our regular post-ers have any suggestions...
Bipolar? (?Narcissistic) Personality disorder?
He should be evealuated by a psychiatrist.