I agree, the fact that her nan helps her with chores at least semi regularly (including garden work) as well as regularly paying for home decor items for her or repairs etc I think she's entitled to state her opinion to her mum about the state of the place. She's definitely a
cat with only child syndrome to the extreme

. Her parents must be round the bend with her!
People cope with chronic pain and other disabilities everyday and manage. I'm not saying it's not an issue but the majority of her problems stem from having no life. She needs some hobbies than exclude going to Asda on a Friday and cleaning on a Saturday.