Does what you write matter to anyone besides yourself? You might never know because very few readers contact a writer to tell them a reaction to whatever they'd read.
Still, that doesn't mean that your words didn't reach someone who benefited from reading them. When one of my stories lands in a new Chicken Soup for the Soul book, I know that it will be read by thousands of people. My story may mean nothing to a lot of those readers, but for a good many, it will trigger a memory or touch their heart in some way. They will be able to relate to whatever I'd written.
Part of what keeps me writing, and probably many other writers, too, is knowing that maybe my words can make a difference in the life of a number of people. Not that a writer can work miracles in anyone's life, but maybe your story can ease a troubled heart, if even for a short time. Maybe your words can teach a lesson to someone who sorely needs it. Maybe your words will let someone laugh. Your words might lift someone's spirit.
It's always nice to hear from readers. It is so satisfying to hear positive remarks from others, but the percentage of readers who contact you is amazingly small. Of course, there are times when you get some pretty negative feedback from readers, too. A reader may vehemently disagree with what you wrote. That's OK. Whatever you wrote made them think, didn't it? There's no guarantee that we'll be liked by every person we meet nor that every reader will love our words.
Make your writing matter to yourself and it is most likely going to matter to a large number of your readers. Give it your best shot. Create a story, article, essay or poem that you can be proud of and it is going to matter to a lot of others.