My parents... a hopeless case

My parents' relationship is a hopeless case.  They don't see eye to eye on anything and they refuse to think about the possibility of separating.  My dad chooses everything in the house and my mom wants to convince me that she is convinced abou the choice.  It is disgusting.  They are choosing wood flooring for their room.  My dad wants one flooring and my mom wants the other.  She has been looking for people who will side with my dad so that she will be convinced that the flooring that my dad chooses is the right flooring.  She finally got enough people who find my dad's choice to be the better one and now she argues that if so many peolpe are deciding on my dad's choice then it means it is the better choice.  So as I understand it other people decide better than her what she likes.  I told her today you are trying to convince me that the square is a circle.
Also this morning she told was saying in front of my dad that so what if she chooses HER choice, that he nagges all day long, that so what if he nagges a little extra.  I defended my dad because that is so stupid and rude to say.  I cannot this is how they decide on things.  If they cannot decide together and they know that they compromise to one another why stay together.  It would be better for me if they stay together but eventually it will be disastrous for me.
This exact episode happened when my dad bought a car.  She bought the ugliest car just because my dad can pay money and buy it.  He was not convinced and she was not convinced. They bought it as a status symbol.  Incidentally this was the start of my fall into suicidal depression.  I could not swallow the idea that my mom who buy a car that she is not convinced of. And she thinks that my dad bought it for her because his wife she is entitled to buy any car she wants even if it doesn't justify its cost.  I eventually got over it by not using the car and until now, 2 years later, I do not use the car.  It just brings me so many memories of pain and hurting that I cannot use it. Also by not using it I was able to overcome the problem by seeing that even if my mom doesn't love my dad at least she loves me.  That gives me solace.  Incidentally if I feel that my dad loves me then I might feel differently but I don't think that my dad loves me or loves my mom and that is heartbreaking.