My mom slept around for 20+ years of marriage, was emotionally abusive to her kids, and never did much if it didn't further her public image. From the outside she looked great, but now she is on the never talks to me again list. My dad was the primary breadwinner by a large margin, cooked dinner every night, coached multiple of our sports teams, taught us to drive, volunteered at our school several times per year, and was so calm I can only remember one time where he lost his temper. He basically raised us as a single father and never wanted to divorce because he was determined to break the cycle. He sounds fake when I type it out.
The settlement after two years of lawyering, and only one of the kids being not an adult at 17 years old, was ridiculous. He took on all of the debt, took care of all the kids, paid all 3 kids child support until we were 21, paid my mom alimony of over $2k, she took half the shit out of our house, and gave her a free basically new car. Oh and he paid for her apartment for a year. This was after talking the judge down for months.
We were firmly middle class, like $150k gross in the 2010's when this played out. I had to pay for our groceries a few times because of this fucked up system. It basically fucks the good parent into the ground for a sense of equality.
It was about 70/30 in my mom's favor. The big problem with no fault is it massively favors the mom.