Your model looks satisfied with her choice of attire for the charity function you'll be attending.

However my wife does look pretty good when she makes an effort, which generally only happens when other people are going to see her. I don't count.

This is regrettably common in marriages. It's the flipside of the security marriage is thought to provide. The entire point of the institution is to make ending it difficult which is why people tend to stop being on their best behavior. Our culture would benefit from some type of realistic discussion of what long-term relationships are really like and how their pitfalls would be best avoided.