Even if the husband realizes that he can t do the job, imagine how bad that must feel for him. He possibly took great pride in his financial acumen. Now, it has been ripped away. He may react with depression, anger, loss of self esteem or withdrawal. What a mess.
Most people have many roles they play in their families and in their lives.
A brain injury can disrupt every role in every facet of their life. The disruption can be cataclysmic. How a family deals with a brain injury depends a great deal on how functional it was before the injury. The healthier the family, the more open they are to help and hence, easier to deal with. Of course the reverse is also true, the more dysfunctional the system the harder it will be to work with.