You're getting a window into just how much it sucks to be disabled and then have extra burdens put on you. I don't know this author, but I know someone else in a similar position and I absolutely understand where this anger comes from.
The anger is not unjustified. Directing it at people who are nearly as helpless as you in the situation is not justified or remotely helpful.
(I'm blind myself.)
Regardless of the condition of your life, harboring anger and malice never leads to fulfilment.