Hi Jim, thanks for your thoughtful post and comments. Yes, my desire to return back to the UK is primarily based on medical concerns and 'what if?' questions about my future years. I do have estranged family in the UK, who I don't expect to care for me. Being of limited financial means is a blessing, because the local authority is required to freely provide care assistants etc if needed. Although I speak fluent Thai, I'm not so sure that I can fully trust 'the system' here to provide good palliative care, morphine etc to reduce pain.
As a scientist, I do know how to end my life painlessly (jump off a tall building lol). If I were to slowly 'degrade' in the UK or Thailand, then I certainly could make provision with various substances that would enable me to end things quickly and painlessly.
But in any case (as previously mentioned), it seems rather difficult to actually return to the UK because of the lack of rented accommodation in nice localities. I could certainly rent in Blackpool, and from a visit a few years ago, it's not too bad a place. But I prefer the West Country.
Right now, I have stopped actively searching for a rented property in the UK. I have decided to stay put one more year in south-east Asia (not necessarily in Thailand), and save up about $20,000 from my online teaching, then return to the UK with that money, which would allow me hopefully to rent a place by putting down several months of deposit. (I don't want to return to the UK without enough funds in case I have to stay in an expensive Air BnB for a few months).
Anyway, plans for our latter years is something that everyone must consider. Best just to drop dead (as my dear father did at 89 years old).
Update: Your friend has a problem and conflict of interest, having a Thai wife and kids. I have grown-up kids and ex-wives (3) who only loved the money that I earned in my previous career as a space scientist. I wouldn't expect any of them to lift a finger to help me!