For me, bringing Ice Cream back would really break my momentum. Especially the activity of going to get it. Straight sugar like that is a slippery slope....
Your wife didn't have much to loose but if you do what she's doing, it might be your undoing.
Like I always say, once you're full you're full. Just fill up on lots of low carb foods as best you can with maybe one or two sushi splurges...