I haven't been poor myself, but I'll offer some weak evidence in favor of a weakened version of your thesis.

I've seen a fair number of people say that when they were children, they were poor but didn't know it, and they were happy. This suggests that (presumably above some level of destitution), low relative status affects people more than absolute wealth. I can't remember whether being poor but happy as a child is correlated with living in the country, but this wouldn't surprise me. It may also be true that children are better at being happy than adults, and this could be worth some study.