There's a word for that, it's solitude. My native language lacks a word for choosing to be alone, which I think is a flaw.

I like to take my dogs for a walk along the canal close to my home, it's very seldom I run into anyone and even then it's usually just a greeting and moving on. Very good time for self reflection and mental decompression. Plus my dogs love it, one of the two uses the opportunity to hunt for mice and the other sniffs anything he can find and he licks the morning dew off the grass. Good times all around.