That's what I think perhaps some are calling ignoring.
My personal thoughts are that all people want to be acknowledged. It is possible to acknowledge a contact from anyone without engaging in an ongoing discussion. A short "ok" does not show weakness. And there certainly would be nothing wrong with waiting just a bit to send that response.
That being said, I've received messages (phone, email, or text) from friends in the past and not been able to respond in the same day. They don't get angry, they know that I have a life that sometimes precludes being able to respond immediately.
I assume that you are wanting your wife to know that you have a life outside of her. Of course the easy way to do that is to actually HAVE a life outside of her. One that will sometimes allow for an immediate response to her messages, and one that sometimes will not. But always one that will at least at some point acknowledge that she has contacted you.
The obvious exceptions for me would be messages that are accusatory or ranting.
Bill
"Don't tell me the sky is the limit when there are footprints on the moon."
