Some harsh words, Kurt, but they could well be on target much as you don't want them to be. Seems that maybe you need to talk through why your wife is interested in the trailer then take the time to calmly communicate that a trailer that size will mean a new truck and the cost of modifying it for the 5th wheel, plus the expense of towing something that big. Then maybe visit your local RV dealer to shop for smaller units that might work with what you have for pulling, just to feel out the market, and if one of those "fits" for her then start checking the used RV market. This is the time of year when a lot of people dump what they have for what they want, or those who bought new and never used the unit much finally decide it's time to part company with the money pit, at least in our colder climate. Another option would be to rent an RV for a few days, or a few long weekends and let her try one on to see if it works for her. If you've never owned one your wife may just be ripe for the adventure of travel, and thinking that an RV would be exciting and romantic vs alternatives for travel, or just wanting to get away once in a while, period. However you approach it, your emphatic "NO!!" is not a smart response in a healthy marriage, IMO.

Good luck with your problem. Hope you get it worked out the way you want it to be.