Songwriting (great songwriting) is hard. Great lyric writing, specifically, is apropos for this comment. I will mention some things that struck me as having potential for improvement.
Two hands on the wheel, heading South in the rain
There's a white line to the unknown
>>>”There’s a white line” is slightly weak and "to the unknown" is stronger. If I suggest a lyric change, I am just giving an example improvement of something that pops into my head. You, the writer, could spend hours, days, on a single line. I write the following with not much attention to your meter, but IMO, possibly better…
The white line embraces (or points to, leads to, etc.) the unknown
You could make something up about the white line being a separator or a line that keeps two opposing forces separate. Or two forces attracted to one another. Doing that in one phrase would be a challenge, but you get the idea.
And a dozen red roses on the passenger seat
>>>It may be fine but might could improve. Perhaps something like…
And a dozen red roses riding shotgun
And a dozen red roses where I want her to be (in that seat)
Make something up about the dozen red roses looking lonely in that seat.
I'm so tired of being alone
>>>This is trite, it seems a bit boring. “I’m so tired of being alone” just doesn’t work for me. Jason Isbell wrote one of my favorite songs and wrote essentially what you wrote except the word “traveling” changes everything; the verses about him traveling alone lead to his chorus of being tired of traveling alone. “And I’ve grown tired of traveling alone, tired of traveling alone, I’ve grown tired of traveling alone, won’t you ride with me.”
Please, please, oh please, may each passing mile help my soul awake
>>>"Help my soul awake" bugs me because it would seem to me that your soul is already very awake; are you not wishing for her soul to awaken? Actually, her heart might be a better target in a song like this.
It ain't easy, Lars, keep at it! Lyric books could also help.
Yeah, you sing fine for singer-songwriter stuff; some of my favorite artists are not singers. Neither am I! It doesn't matter so much if one writes great stories in song.
Your guitar sure sounds great, nice! Good luck!