the person doing all of the alleged caring is left feeling hurt or resentful or upset at ingratitude etc. because the recipient of the caring does not then act in a certain way, or others just in general do not act how one might want in response to any number of things designed by the actor to be generous, giving, helpful etc. and instead of trying to change the ungrateful, I think it is is simpler, more direct, and more likely to succeed if one stops focussing on them and starts focussing more on oneself.