I think why the occurrence of spousal murder has been on the rise is because most people in abusive relationships are silent about it. They put on a facade that they are happy whereas they aren't. They bottle up so much until they get to the point of venting their accumulated anger on their spouses.
Whatever the basis of their anger, the love they once professed should not hurt.
Yeah, you sure have a point but I still don't think it's enough reason for anger to drive someone to kill another especially a loved one. God help us. Thanks sis @evashinen