My wife gets angry when I call her pet names. Apparently Sandwich Making Machine is sexist.
Have you listened to what she said? Did she tell you why she doesn't like it?
I have, she said Sandwich Making Machine is sexist because it's demeaning. But my friend said to me, "what can you expect from that mouth breather? She's just your wife!"
I agree with your wife, that calling her Sandwich Making Machine is sexist, because it implies that she's simply an object that does things for you. Your wife is a person, not an object, and it isn't good to say things that dehumanize her. I think it would be good if you listened to your wife instead of your friend.
But I think my friend is right.
Well, you're not married to your friend, are you? I suggest if you want to save your marriage, you should stop objectifying your wife.