If that is the case, then you should have said that in your original post, instead of making snarky comments about "I can only assume you're trying to save money" and "It won't cost you extra", etc. You stated you have a physical problem which prevents you from understanding, yet it didn't occur to you that she could have a learning disability or some reason for her spelling? I'm not saying that is the case at all, merely stating that you also did what you are complaining about - you made comments without taking into consideration the possible reasons.
There isn't any reason to be rude or judgemental. If you can't understand a post, don't respond to it.