The cases are totally different insofar as the cause of action is different. Only a few American states allow a plaintiff to sue for alienation of affection which actually has a person seeking restitution for infidelity.
In the Canadian case, the plaintiff (scorned wife) is suing the insurance company for damages resulting in failure to supervise an employee - the infidelity is a by-product of failure to supervise.
Personally, I’m all for suing the mistress/infidelity partner - cause remember, hell hath no fury like a woman scorned (or man!).
Why not get a little back from the person complicit in breaking up the marriage. Though, by the same token, I’d take the ex-partner for all they were worth as well!