Like I said before sometimes simply taking a word out or switching where it is on the line will sound better and flow better. So your first line would sound better as "What if yesterday I had to die alone" because the second line doesn't make sense, maybe "While I was walking on a path astray"

What if I had to die alone tomorrow,
With nobody here to ease my sorrow.

That sounds much better see what I mean. Message me when you fix them up the way you like them and I'll come back to vote the new versions haha