I will agree with others that while TM/SM may have been lazy and hoarders, there is also a possibility that depression and just finally breaking were part of it.
When my ex husband left for me for his much younger co-worker, I went through a bout of depression I thought would never end. Having to find work, caer for 6 kids under the age of 14, bills, the house etc etc., the one area I let go was the house. The laundry room went first, the mounds of laundry reminded me every day of what a failure I was. Before this I had a very very clean house. I cleaned everyday. As soon as the kids clothes came off for baths, it went in the washer. When they went to bed I cleaned floors and kitchen and bathrooms. I was embarrassed and allowed no one in the house. It just was too much and when it started to pile up it, wow...it really was too much for me.
Thankfully, I was able to get back on track. It started to go downhill within the first 2 months. It was really bad by month 3/4.
Not defending them in any way, and am assuming that it could be that they normally lived like that, yet am open enough with a life experience that tells me there is another option.
Kelly