Rather than spend time going round in circles why not start fact checking, most info is online, including the interviews and forms, costs , etc that you would have to in order to get a Visa.
(Unless your son is an American Citizen I don’t think that he will be able to sponsor you)
You can research health care costs online.
Also research areas you would want to live
At least when your husband starts on about it again you will have a list of answers to all of your questions.
We looked into staying in the US for 3 months a year, but due to DHs age and various health issues the Travel Insurance costs were horrendous.
I agree with the others, rent over there and keep your UK base.
I hope you have a lovely time though, it’s a great place to be.