I have to say I agree with you.
When you are a truly "Good" person (and that whole phrase is very fuzzy), but when you truly care, and you do good because it comes from the heart, when you are trusting, are compassionate and empathetic, it gets to the point where shit eats you up. In all honesty, when you are "truly good" people take advantage of you a LOT (not just money, either, they'll hit you up for favors, they'll ask to crash on your couch, they'll eat your food and drink your booze and never bring any over, they'll hit you up for car rides and never pitch in for gas, they'll pawn off their kids or pets on you ... you get the point). However, you can't operate from your heart center on a part time basis.
So a lot of really kind people get to the point that they avoid other people entirely, saying no is very, very hard, but not trusting is impossible, assuming the worst in a person's nature feels ugly. You get to the point where all you want to do is crawl in bed and hide.
Being successful financially generally requires you to make some ruthless decisions so its rare that you find very, very successful people who are selfless and kind.