If she was "suicidal," then how come she's alive and the children are dead? Doesn't sound suicidal to me at all. She was depressed, something the article said happens to almost half of women after they give birth. How can you hold the father responsible for leaving his children with his wife when she's never given any notion of HARMING the children before??? He's only responsible if he KNEW that the children were in danger from their own mother, or it was pre-meditated between the two of them (which if it was, they're doing a fantastic acting job.)
Anyways, put her in a mental institution if she's clinically deemed to be "insane." If she was completely in control of her own faculties... Get rid of her. I wouldn't want my taxes paying for some mother who maliciously kills her own children.