First, "loathe so much" is a misrepresentation. There are certain aspects of the US that I loathe and certain aspects that I very much appreciate. Unfortunately, under 25 years of the reactionary Repug rule, the former are much in evidence whereas the latter are becoming an endangered species.
Then, there are expectations and reality. I always wanted to live in NYC, and ended up in Baltimore. It is not the best city to live in (as many US cities) - not horrible, to be sure, there are much worse places in the world, but there are also much better ones. Rather than being horrible, Baltimore is annoying - poor infrastructure that makes moving around difficult, ubiquitous car-related noise (police/ambulance sirens, car alarms, fortuitous honking, loud music, loud trucks and buses, police helicopters) which after a while make a person very tired, general disregard for cleanliness, mounds of trash, hordes of vagrants and junkies, high crime, lack of retail shopping (shopping for most necessities requires car trips to the burbs). Having to deal with this shit every day is not compensated by what cities like NYC or even Philly or Chicago can offer. Baltimore has a nice culture and recreation scene - to be sure - but a big chunk of it is sports and the waterfront which is like a big fraternity row. In short, Baltimore is large enough to raise expectations, but not large (or developed?) enough to fully deliver on them.
At the same time I do not have much other options - moving to the burbs is out of question, I find that landscape and life style that goes with it too depressing. I cannot afford moving to NYC, and besides I like my job and I would not want to give it up prematurely. So when Baltimore annoyances pile up over time and I realize that there is not much I can do to change that - I feel trapped - and depressed.
Thomas Seay mentioned that bitching is the common currency of expat communities - and he is basically right. This has been my observation as well. However, I have almost zero contact with expat communities - I just cannot stand them. It is not just the constant bitching and myth making but also their refusal to adapt. If I wanted to be in a Polish community, I would have stayed in Poland. But I did not, and made a conscious effort to adapt - which involved inter alia cutting ties with expat communities. I still have a few friends (who btw also adapted) but that is different than a community. So while Thomas is basically right, I do not think his explanation applies to my particular case.
He might be right, however, about the Shangrila expectations - which are not that unreasonable given this country's resources - and the rather bleak reality.
So to sum things up, it is my particular life situation, being tired of everyday annoyances and feeling trapped, combined with the particularly poisonous political climate which no reasonable person would find acceptable anyway - rather than general loathing of the entire country. It is a big country after all, with a lot of diversity - and being a philosophical nominalist by nature, I have always been suspicious of general concepts.
PS. Going back to Poland is out of the question - I realize that each time I visit my parents there. Way too pretentious with too little to back it up, and their politics make the US politics look like a decently run public affair, while their in-your-face Catholicism is as bad as the most poisonous forms of religious fundamentalism found here, but much more pervasive and difficult to avoid. And their rabid anti-communism - they tar and feather people like me.
Wojtek