when I worked at another forum, we tried very hard to break up posts into paragraphs to make reading easier, and would change the color of text if it was difficult for us to read.
I have had ON several times, and my optic nerve is just so sensitive. I can no longer read many great books, and I can no longer watch vivid displays on TV. My new TV has a vivid color setting that makes things jump off the screen at you, but it kills me to watch it. I have to back it down to a normal display.
I think a bit of education should help her. Since she herself isnt affected, she may just be trying to be more cheerful with her colorful posts, and doesnt realize that we need breaks in our conversation, even if grammatically incorrect.
I frequently skip posters that have long drawn out paragraphs with blazing colors. That may explain why you were one of the only ones responding to her postings.
your a good egg!