The reason that this sort of self-serving exercise in demonizing her children for not wanting to feed into her martyrdom complex is important in the here-and-now is that we don't really know what Mike's objections to her being at work all the time are. We get some broad hints as to what the real problem is every time she gets into a snit about how her children's very real need for just a moment of her time to see if she actually likes them 'actually' means that they're selfish, chaos-loving parasites who hate HER and want HER to not have an identity because they're parasites who hate her and love chaos. Mike could actually have made an aside about how nobody asks him anything, they just tell him to do it and if he doesn't, he's a bad kid who is bad. Since Elly is a jerk propelled by self-pity, she can't help but assume that Michael's wanting to have some input into what his life is like means that he wants to enslave her and take away her identity.
Well, there's that and the fact that Elly is clearly upset that Michael wasn't sympathizing with the person he should have sympathized with. All he cared about was some irrelevant sick child who only got sick to take away the real victim's identity. Had he worried about someone important like Elly, he might have stood a chance of having his words and actions depicted with something like accuracy.