my father's shaving brush

The bristles are falling out of my father's shaving brush. Except it's not really his, it's mine. His one, which he used as far back as I remember, had a wooden handle and real animal hair - horse, was it? Or pig? Over the years, it wore down until it was just a prickly stump a couple of inches long, but he hung onto it, even after he switched to using that spray-on stuff with a minty smell and the consistency of mock cream. I don't know what happened to it. This one has a plastic handle and nylon bristles; I bought it for his seventieth birthday but I don't think he ever used it. He died only a couple of months later and it was returned to me still in its packet. So I've been shaving with it, off and on, ever since. Sixteen years next Tuesday. He would have been 86, an inconceivable age for someone as wrecked as he became, though his brothers - one older, one younger - are still alive. I don't know what to do with it, the 'new' one I mean. The way it leaves nylon bits on my face is intensely irritating but it has some kind of weird status in my mind, as a memento mori I suppose. Perhaps I should put it away in the bathroom cupboard and just leave it there, the way his old animal hair one was left? Or should I consign it to the beyond?