Why is Gravedigger your favorite song? Is it the melody, lyrics, or something else?
It is a slow song and strictly acoustic, it came out in 2003. Talks about digging grave and making it shallow to feel rain.
It is a sad song indeed. Any other favorites from Matthews, possibly more upbeat hits?
Yes of course like greystreet is a good one. Most of his songs are a bit subdued though. 
Very true, have you ever had the opportunity to see him live? I believe they are still touring.
No I have not but my wife did before we got together. He actually was only one to perform and saw him give 2 performances so he played for like 3 hours
Sounds like a great time. Do you recall when you first heard them play or who introduced you to their songs??
I would say late 90s. The gravedigger came out in 2003 so that was when I graduated high school. Unfortunately he doesn't play this song much
That is fantastic you've been entertained for so long. Do you know how to play Gravedigger on any instruments or have you memorized the lyrics well enough to sing it?
I can probably sing it well enough although the song is more like four sad stories all in one so trying to remember them would be a bit tricky. I haven't tried on my guitar though