When a child is first diagnosed with autism or aspergers, parents read all the well-known text books, are referred to the same websites, and advised to use the standard autism parenting techniques. With the correct diagnosis, luck, early intervention, support and services, the child will hopefully be helped to achieve his or her full potential. For most families there are lots of speed bumps and meltdowns along the way, because every child is different, and what works with some, does not work with others, despite the insistence of autism service providers.
But sometimes things are very difficult indeed. It could be the severity of the autism, challenging behaviour, multiple diagnoses, or any of the other slings and arrows that get thrown at families, who sadly are often blamed when the child's progress doesn't go to plan. The implication is that the parents are not "strong enough", don't try "hard enough", are too selfish, too selfless, too useless to be able to help their child.
Sometimes it's because they haven't got the right information.