In loving relationships it’s mutual. Wifes would probably also kill for their husbands. The division of labour would also be split somewhat equally.

When one would do labour or killing depends on context. I’m more likely to accept some labour on request from my spouse, than i am to accept an order to kill their enemies. But we are still honest when we say we would kill for eachother. When it would make sense, in some extraordinary situation, that is. I don’t expect that hypothetical situation to ever come up though.