Denial isn't as pretty as martyrdom.
Perhaps that's why the aggadah I grew up with to explain Yitschak's blindness had angels crying burning tears into his eyes. He had lost his sight when he went up to be sacrificed on the Mountain That God Showed his father. Upon seeing Avraham raise a knife to slaughter his bound son, the story went, the angels of heaven crowded above Yitschak's head and sobbed fiery teardrops. Ever since that day, Yitschak was unable to see.
Aggadah number 60 in today's selection includes a version of that classic tale, but as an afterthought. The bulk of the section explains our middle patriarch's blindness differently. It portrays Yitschak blinded not by the trauma of the akeda/binding, but by the sins of Esav and Esav's wives. Esav's wives worshipped idols? Then like a man closing the windows of his house to keep his neighbor's smoke out, Yitschak's eyes weakened of their own accord to keep him protected from the sin. The neighbors had begun talking about what a wicked man Esav was? Then God blinded Yitschak so he would not be able to leave his home to hear it.
Blinded by denial... sort of an obvious metaphor.
I'm not sure why God would be portrayed assisting it, though. Maybe Yitschak was so fragile he couldn't handle encountering sin -- another trauma from the akeda? There is that traditional view that Yitschak had the status of an object consecrated to God, and therefore could not leave the land of Canaan. Maybe he needed to be protected from other lands, too.
But what's the point of such fragility? It would render useless a prophet or a teacher, and certainly a chieftan. So maybe Yitschak wasn't supposed to be a prophet or a teacher like his father, or the head of a clan-becoming-a-nation like his son. But what then was his role?