I'm also an INFJ atheist. You could call me spiritual, but I am in no way a supernaturalist.
Atheist means "non-theist" in the same way asymmetrical means "non-symmetrical." It's not really a label that tells you what the atheist does believe in, just what they don't believe in. For example, some atheists do believe in "something else" such as life after death or reiki or The Secret or whatever. Other atheists (like me), not so much.
In my experience an atheist worldview can be rich, meaningful and poetic. It might seem counter intuitive, but I have felt so much more spiritual since embracing naturalistic atheism. Each to their own!