Unpopular opinion: being alone on any car ride - long or short - is often better than having someone travel with you.
I love being alone in the car. I can space out and think through story elements, characters, histories, even random little interactions that may or may not ever see the light of day. I can cry when a song makes me think of emotional turmoil one of my characters is or will go through (or that I went through). I can belt out as many or as few songs as I want as unabashedly as I wish. I can even listen to half the song and only sing the chorus if it suits me.
There are times where I purposefully run an errand by myself because I just want to listen to a song completely uninterrupted. Or I want to listen to a song because it makes me hop right into a moment with a character or plot out a scene.
Fun fact: most of the time I 100% love being alone. There are, undoubtedly, days where I find myself wishing for human interaction outside of my family. I work from home, so 99.9% of my daily interaction is with a family member. (And honestly, most of those interactions are with the dog).
With my drive to college almost exactly 5 hours long, I spent many of those drives crafting story ideas. Listening to songs on repeat without fear of judgement because that 30 second segment in the middle just reached into my core and yanked out a scene that I'm trying to flesh out and only that 30 seconds seems to elicit any semblance of a continuation. I can't stress how many times I've had a song in my library for years and suddenly it will spark a whole new level of creativity in my noggin. I can work through dialogue by legitimately speaking to the empty car without someone thinking I'm nuts. They have every right to fear for my sanity, but at least when I'm alone there's no one actively staring at me like I'm a crazy person.
Most of my friends think I'm weird (but they love me anyway), because I'll be happy to travel and visit them. Even if it means a 6 hour road trip by myself. Because dangit I am happy! I get to sit and think without interruption. No one comes into the room and starts asking questions or favors or opinions. I can just think.
I am alone with my thoughts and it's a beautiful thing.