Yes, you are being treated poorly. If you are ignoring Diplomacy, these are the consequences. You can take it personally if you like. One sided deals is a pretty bad sign for your future relations. Try changing your tactics/strategy next time and see if there is any difference. It is interesting that the AI is actually responding to people and some see it as being broken. I have seen that with other games. You, at least, are double checking. That puts you way ahead of the crowd. Diplomacy and Ideology are supposed to be much more impacting nowadays. I go strong Benevolent at first and it shows with some faction, then, when I start taking other choices as well, we are no longer such best buddies. Still figuring it all out myself, but that how it is working for me.
Early Open Borders is the only specific practical advice I have found so far. It helps a lot.