It's an unanswerable question really. The short answer is that I chose Thailand because that is what I wanted to do. After spending 6 months of each of the last two years in Chiang Mai, I will, all being well, shortly be moving to Thailand permanently.

Which raises my best piece of advice. It's obviously difficult for you with your responsibility for your mother, but before you make a permanent move, try to spend at least one or two extended periods of 3 months or more in Thailand. It's not the same as being on holiday.

There are as many reasons for living in Thailand as there are expats. Don't concern yourself with why others have done it. Check out whether it works for you, on your terms, for your own reasons and if you are really, really, sure that it does, go for it.