In the summers, I teach ladies and men at Jericho beach , the basics of windsurfing and high wind skills waterstarts too. Sometimes being a patient, kind instructor who doesn't just shout out commands at the students goes miles instead of aggressive teaching style where you actually push the person onto the board... Paid lessons can still be poorly instructed. Do your research and find the kind of individual instructor that suits the learning style.
I believe anyone can get a waterstart in less than 3 hours in steady (not gusty) conditions with not too big of waves. Berkeley marina, California worked well for me. Go somewhere where there is a rescue boat on hand like Berkeley - it will help calm the nerves in deeper water knowing that you can forget the world and just focus on the waterstart. You really do just forget your surroundings when you are "all in" , which is needed to really feel, and get this.
For me, I had people (good windsurfers) barking instructions at me and it really does not help when you hear the same thing the 10th time.., It is very annoying and tone matters a lot too, I find. I also don't like learning skills from a boyfriend. Teacher voice = sooooo aggravating, depending on the person ofcourse.
For rig handling, help her carry to the water if its too heavy. I'm curious what size board and sail she's using.. For her size, you could go for 18 kts steady wind, 4.5 sail, and a 120L board, and adjust if needed.
Did you try showing her a way to getting the rig out of the water is to grab the mast and think about perpendicular wind angles. If it's not perpendicular, you are fighting the wind when you want to work with it! Then, once the rig is in place, just give it a little jiggle for 10 seconds and voila! no strength necessary. This being said, swimming lessons and general fitness and conditioning goes a long way to make everything easier. And, helps with confidence in the water to be a confident swimmer / water treader.
Happy to chat with Jen and your wife, also - I can't imagine being stuck on a water start for a year or 6 months. That would drive me insane... your wife is obviously tough as nails and persistent so she can get a waterstart, if she wants to. Maybe suggest she gets involved in a forum like this to ask for tips, instead of going through you? Just a thought--
Cheers, and happy sailing! Sorry if my post is a bit harsh, just think it's important to say it like it is--
I am sure you're great instructor - sometimes third degree separation helps is all.
Linda