Bill is extremely vain and winds up steering all conversations towards himself. When evaluating situations, he can only see how they affect him. Bill may have which type of personality disorder?

narcissistic personality disorder

Explanation:

Narcissistic personality disorder -

It is a type of personality disorder, which includes long time period of some extreme feeling of self - importance and lacking importance towards others.

The people suffering from this disorder tends to spend a lot of their time about themselves and their success and achievements, bragging just about themselves and not listening about anyone else.

The cure for this type of disorder because, the patient refuses to the fact that he or she is ill, making it extremely difficult to cure the problem.

Hence, from the question, Bill too is facing the problem of narcissistic personality disorder.