The reason for this is that the Pattersons don't actually talk to one another about their problems. If Michael, as an example, had said that time simply seems to drag on forever, he would have got an angry lecture about how hateful he is for saying something so manifestly untrue because the oblivious twit jabbing her finger in the air about how hard her life his and how bad his is simply incapable of understanding that hers is not the only frame of reference in the world. Elly impresses me as being someone who never realized that people are individuals who see the world their own way. This means that while she can remember that when she was nine, she wondered why Marian thought that time was zipping by at a ludicrous pace when it was obvious that there were far too many hours in the day, her thirty-five year old self is exasperated by Mike's stubborn, selfish and hateful refusal to admit that there are too few. Realizing that people perceive time as going faster the older they get is an abstraction that her tiny mind simply cannot make.
This obliviousness to her surroundings thus guarantees that Elly would naturally think that everyone everywhere wants to hear her rattle on about her children; since she's obsessed with being a martyr mom, her clueless inability to see that other people don't think like her mean that if they don't especially care about what the Hell Mike did or especially envy her lot must be trying to screw with her out of spite.