I tend to agree with mim on the one-parent/two-parent deal... Yes, ideally we would all be raised by two happy loving parents. The reality is we are lucky to get even one loving parent... those who had two are more and more scarce these days, which was a trend that began a little before my parents divorced in 1977 when I was 5 years old.
My mother was certainly overburdened. She worked full-time and had two children to raise, 5 and 3, by herself. We lived in the ghetto for the first two years after the divorce, and slowly she climbed in her career, making better money for us to live off of, and consequently having less time for us. I was a problem for most of my childhood, my sister slightly less so. I did some wacky things at the school, stuff that I had to have therapy for (or not return to that school).
Would she have benefited having a "partner" raising us? If the partner was an actually interested party, yes! My Dad was not that guy though, and never would be, so she had to do the best she could. Looking back, there were definitely mistakes she made, but in her position I do not fathom how anyone could have done better, or even the same, by herself. She loved us, and paid as much attention to us as she could without losing her jobs.
The "overburdened" thing is a cop-out. She may have been overburdened, but it was a self-fulfilling prophecy of her simply not doing enough in the child's younger years.... She created the overburdening herself, and refused to deal with the situation. There is lots of help available out there... I had a "Big Brother" for years, and it was fortunately a great experience for me, although there have been some bad tales from that program. We went to the Summer Camp for the city kids, bus-riding in and out every day... mostly subsidized so Mom didn't have to foot the whole bill, providing my sis and I an outlet that we resented at the time, but has proven to have been well worth it.
Long story short, there is help out there for "overburdened" single parents, it is incumbent on them to seek it out or rightfully take the blame for their inability to parent their child. This woman has totally blown it, and should be taking the lion's share of the blame.