Some options I can think of
- Have your wife turn off notifications in her app (You can do this in android not sure about iOS)
- Use smart apps that send text messages or modify Smart App to send text messages instead of notifications.
This does seem like something others would want. My wife doesn’t use the smart things app so we didn’t run into this issue but I am sure if she did I would be in the same position. So I am surprised this isn’t a feature.