I had read all OP posts, but not the comments so apologies if I am repeating.
OP, I think you may have a form of PTSD, as I have a friend who I thought was posting this, except for a few details different.
Brought up by a single mum who had severe OCD. The amount of times my friend would come to school with the wrong shoes on, next time the incorrect jumper. And why, because she had left the shoes/jumper/lunch container/socks you name it, laying around. Her mother would pick up anything laying around, put them in a bin bag and she had until a certain time to claim it, if not, then the bag when into the main dustbin. They lived in a flat so the bins were communal, and often raided before she had time to salvage her items. If she had gone home, changed from school clothes and then gone out, and missed the bag dump curfew, she had lost those items. Her mother had a real problem, but it is just how they lived.
She moved out as soon as she could after school. But her house sounds like yours. Any area that someone would see, was immaculate. The guest bathroom, the towels were lined up perfectly and it was so bad she would go in after you and make sure it was perfect. If you got up off the sofa, she would puff the pillow so it was perfect. BUT, her room and her bathroom we were NEVER allowed to enter. One day she was really ill and I turned up unannounced to drop some things off for her. She was furious, and as she was unprepared, I was able to see into her bedroom. It was just chaos, and was like another part of her existed in there.
She has had quite a few MN problems through the years, but was diagnosed with PTSD. She too would spend so much money on personal grooming, always turned out immaculately. She married a much older man (as in 20 years her senior) he was a very patient man, but I think the attraction was that he was well established in life by then, and secure.
I don't think she will ever admit that her childhood was a factor here. She will tell you she had a very happy and normal childhood. It was normal for her though. I could see it wasn't being an outsider to the family.
OP you can try to help yourself and it seems like you have taken on board a lot of advise here. Make the first step and get the sofa. Baby steps going forward, perhaps next month buy a set of towels for your bathroom, or a kitchen appliance.
You are worth more than you think you are.