This is, of course, a ridiculous thing to think. Sure, Liz is an entitled jackass who bleats piteously about how unfaaaaaaaaaaaair it is that she can't barge in and simply be with Anthony whenever she takes a mind to and she might be an immature little twit who selfishly decided to show an unfortunate up at her own wedding because she was mean to her and said bad things about her but she's also someone who doesn't understand what the consequences of her actions are. It always seems to astonish her that Thérèse isn't going to be wonderful and let some pasty-faced blond twit take over her life; to her, having to understand and empathize with the fear Thérèse has of having to swallow her pride and console herself to being a well-kept fool like her mother is like asking Elly to understand that human agency led to April "toppling" into the river. Since Liz combines a blindness to what the effect her behaviour has on other people with selfishness and a lack of empathy, Thérèse is thought of as an irrational, selfish villain.
The problem is that she's not alone in being cast as a monster because she assumes certain facts not in evidence. If you assume that a Patterson is paying attention to his or her immediate surroundings, if you act as if a Patterson has a realistic understanding of the consequences of his or her behaviour or if you look at a Patterson and see a person who can function as an adult, you, my friend, are a super-bad person who is unfair, has to win all the time and leave them with nothing and wants the family to writhe in the dirt as you enslave them in your family politics.
You are also someone who would not waste time trying to enlighten the Patterswine. Not only do you know what futility is, you'd not want to be in their company if you could avoid it. I should think that if the strip were allowed to continue, we'd be dealing with a conversation between Thérèse and some third party in which she realized to her horror that she was dealing with a crazy, stupid person.