I completely agree with Nay-DMAX, you need to go to a place with plenty of space and just practice hitching and unhitching, towing and reversing. There are caravan towing courses available in a number of areas if you google it, especially if you feel better not having hubby yell at teach you. Seriously though, I believe it's very important that you wife knows how to tow the trailer in case something happens to you. On our travels, we've seen a number of women who've been either stranded for a period of time or other people have had to disrupt their travels or work time to help transport the vans when something unfortunate has happened to their usual driving partners. The women mostly say that they wished they had learnt how to transport before xyz happened.
I hitch and unhitch the trailer as well as tow and reverse our 9 metre caravan. It's usually me reversing the van into sites while Firefox stands outside and directs as he likes to get it fairly level before unhitching. Firefox has a handheld UHF that he directs me with "right hand down", "straighten up", "smidge back", etc and that works for us very well. Most of all, if hubby is going to ask wife to learn, he must be very patient until she gets her confidence up. Good luck!!