You have this world of mathematics, which is very real and which contains all kinds of wonderful stuff. And then we also have the world of nature, which is real, too. And that, by some miracle, the language that nature speaks is the same language that we invented for mathematics. That's just an amazing piece of luck, which we don't understand.
I am sure we should not shut our hearts against the healing influences that nature offers us. But I understand your feeling. I think we all experience the same thing. We resent the thought that anything can please us when someone we love is no longer here to share the pleasure with us, and we almost feel as if we were unfaithful to our sorrow when we find our interest in life returning to us.