I can't imagine my families faces, and I prob couldn't even manage a photofit of my own face to be fair. Its strange when you first realise this isn't standard for most people and its actually a thing.

Put photos in a necklace for your wife or something similar if it bothers her.

This matches my experience. Everything and everyone has a feeling, not so much a word, or an image, or a number, but a simple to recall, and hard to explain feeling.

If she's still in that dark place, ask her whether she can recall what your daughter's "feeling" in her head. If she's anything like myself, that feeling is the sum of her relationship with your daughter all in an instant. Not only is that something you probably can't do that she can, it is an interesting way to perceive others. It helps a lot with code switching too, that same feeling of someone else also sets the tone with which you can effectively communicate with them in my experience, though it doesn't work on everyone.

This is the level that I am at and it's hard to explain to people that, "no, I don't remember so-and-so's smile on their birthday." Like the feeling of the experiences are there and an analytical capture is, but vision? Gone the second I don't see it anymore

It's possible that she hasn't got aphantasia, but something called face blindness (prosopagnosia). The Wikipedia might be an interesting read for you guys!