I wish you all the best in your endeavors!
I'll offer up another nutritional option for the mix less radical for the mix (I was influenced by your husband's health status) and a tad more "starter", and therefore more achievable/sustainable, but with good results too!
And that's the "Fasting Mimicking Diet'.
It was developed by Professor Valter Longo for cancer patients and does what it says on the tin.
You get 1100 calories the first day, then 900 for the next four.
Low Carb (Longo's Prolon pack strangely quite high carb`), low protein and high fat.
Eaten before the evening. You do it 5 days a month for 3 months and there should be improvements.
It's definitely still a fasting experience but you get a lift of some food every day.
This lady 'Dr Mindy Pelz' included it in her resetter group and has a slightly adjusted less carby version of the protocol;
Whatever you do I hope it works well.