I think there's a typo here, otherwise there may be grounds for divorce...Yes, I think they both need serious psychological help.
They are perhaps one of the most dysfunctional couples.
No matter which way you look at it, even if one is inclined to full believe that Rebecca was truly this unquestionably, horrible, vile, evil person, when it comes down to it, Maxim murders his first wife, because it is easier than getting a divorce, and he did not want the scandal of a divorce.
Not the mention that fact that it is not just that Rebecca was such an awful person, she had been since the start of their marriage, the thing that really pushes him over the edge was her implication that he was pregnant, so untimely when Maxim shoots Rebecca it is really because he wants to kill the unborn child.
And the narrator, is completely unphased by the fact that her husband offed his first wife because he no longer wished to be married to her, she is just thrilled to learn that he never truly loved her.
You would think she would be at least a little concerned about what would happen to her, if she displeases Maxim.