I just read a post by the author Ian Brown, "The Absence of Normal Frees Us" about Brown and his son, Walker. Brown's book, The Boy in the Moon, describes their relationship in greater detail, but this essay alone is well worth reading, and perhaps a good place to start thinking with Brown about the meaning (or absence of meaning) in Walker's life:
I couldn't tell, and so I spent a lot of time looking for some way of justifying his life, lived as it is in semi-darkness. I found proof again and again, if only I remembered to look in the right places. Walker's life is not a success measured on any conventional scale of human success: he is never going to earn his living, never mind an income big enough to buy a fancy retirement home for his Mum and Dad; he is not going to go to Harvard or anywhere else that will make his parents proud; he is never going to invent a faster, easier way for people to spend money on the internet. The value of his life, if it has a value, will have to reside in his life, per se, in the sheer fact of his existence.
It's the very lack of so-called normal expectations, the absence of the possibility that we can ever "achieve" much or even disappoint each other, that frees us to be ourselves with each other, to remember who we are and what actually matters, as opposed to what it supposed to matter. That is a great, great gift—and I say that as someone who hates to use the words "disability" and "gift" in the same sentence.
I commend Ian Brown's essay to you, and I'd love to hear your thoughts on it.