Those who dish out can never take it. Some can dish out, some can take it, some want nothing to do with either side. But there's no such thing as a person who can do both.
A person who accuses another of being selfish or ungrateful is almost always trying to get something specific from the other that they don't want to give.
The label of stubbornness really means "refuses to do or be what I want them to do or be." This label tends to follow statements that start with "you should" or "you shouldn't."
Cries of "I don't understand!" means that the person wants to rant at length in vehement disagreement against whatever they don't understand. They don't want to actually understand.
Cries of "I get it!" means that the person doesn't get it at all, and is probably so far from actual understanding that they never will. Especially if the followup starts with "but you have to understand..."
Accusations of any character flaw means that the accuser has that flaw. These can be very revealing about the weaknesses of the accuser.