I don't have a suggestion for a particular bike though I think the CAAD isn't the best choice if you can have only one bike and want to ride year round.

Though this probably will fall on deaf ears, I feel obligated to say it. If things are tight financially, and getting a new bike means going further in debt, you OWE it to your wife to take a serious look at the used market. It doesn't mean you have to buy crap. I'm sure the bikes you owned before were decent bikes and they're still decent bikes even though whoever you sold them to bought them used.