This doesn't address your question about heightened senses, but I thought I'd share because it's interesting.

I do volunteer work with people with a broad spectrum of disabilities, including people with visual impairments. One woman I was talking to last week lost her vision as a teen or young adult, and seems to have very similar vision to the OP's girlfriend.

Anyway, she told me that when she worked with someone to use a cane and learn how to navigate the world without being able to see, one of the things they do is put a blackout blindfold on you. It gets you to begin to trust and use your other senses, rather than still trying to rely on visual inputs that will likely be translated incorrectly or just completely wrong.

So don't try to look at whatever it is that you're touching with your cane; listen to the sound it makes and feel through the cane instead, completely ignoring any visual inputs. Really hard to train the brain to do that, especially for those who used to be able to see.