I'm a new TI owner and would definitely encourage you to get one and enjoy it with your wife. I'm really sorry to hear of her suffering and pray that she will have many great times with you on your TI. It's a great craft for taking out kids and others who don't need to peddle or paddle.
I'm up in Washington but if I were in your area I'd offer you unlimited use of my TI. Maybe some other TI owners in your area would also offer to share theirs so you can enjoy it while waiting for yours to arrive.
As for handling launching chores alone I can affirm that a trailer makes it a snap. I'm 66 and have no problems to launch directly using my home built trailer from a boat ramp. Here's some of the details of how I built mine. Total cost was under $450 and I only had to make one change, adding a roller/support under the aft end of the trailer to strengthen the lattice.
Many thanks to DogsLife for inspring me to build my own version of his trailer.
Finished up my trailer last week, it cost me about $400 total. I picked up my new Dune TI from Next Adventure in Portland on Thursday and went Sailing Friday and Saturday on Lacamas Lake about 2 minutes from my house. Lots of fun and lots more to learn!
Folding the Harbor Freight Trailer for storage is not practical. Taking the fastening bolts out to fold up the Harbor Freight trailer is way too much work, in my opinion. Not to mention if you have added the 3/4" plywood deck, 4x4 beams and 4'x8' Poly Lattice for the TI Cradle. I like just having the TI fully loaded and ready to sail. I'm waiting for my cover to come in and then I can even leave the seats and cushions in. I bought two Stearns Flotation Cushions which make the seat more comfortable and elevate me about 2-3" more above the often wet deck.
The best reasons for having a trailer for your TI are:
1. Don't need to take off the amas, just drive up the the water, install the seats, step the mast, drop in the drives and go! Even an ancient rookie like me can do it in 10 minutes.
2. No need to remove the TI from the trailer to store it, the bunk will cradle your baby nice and soft, no worries about deformation when storing on a rack, etc. I ordered a cover to protect my TI during transport and storage.
3. Easy to change vehicles (my wife prefers to take her car when we travel) so I can use any car with a 1-7/8" hitch ball. I priced getting two sets of roof racks and it was more than I paid to build my trailer, not to mention that then I'd have to buy and rig a Garage Gator to lift it.
4. No massive strain getting the TI up and down from the roof. It's about 200lb loaded up. The trailer is high enough to allow me to install the cart in the rear scuppers and just slide her off the trailer. I know you youngsters are happy to flex your muscles but I save my strength for the tennis court.
5. Less danger of damage loading/unloading (both to myself and my TI). Also probably will get better mileage towing than car topping.
I'll post some more photos of the finished trailer on this site later. Meanwhile, here are some shots of the materials I used and base structure of the unit.
This is the almost finished product, simple design: 3/4" plywood deck bolted to the trailer frame plus 8 ft. 4x4 lag screwed to the deck.

Lag screws through angle iron:

Front view:

4x8 ft. plastic privacy lattice (denser than standard lattice):

Exterior screws to hold lattice to 4x4 beams (easy to screw below flush):

Since this trailer is too short to handle the TI I added an 18" extension from Harbor Freight plus 72" heavy duty safety chain.

Here's the finished trailer with the TI loaded. Note how the Amas are supported:
Let me know if I can help with any questions.