edit - Thank you, community. Someone had the right book, I really cannot that you all enough!
This has been bothering me for years and I never finished reading the book. When I was younger (around 1994-1996) I read a young adult book about a youth who finds a ring in graveyard. They put on the ring and spin it causing them to go back in time (if I remember correctly the youth only goes back to the 1880s). When staying in the graveyard they are a solid person, when they leave the graveyard they become like a ghost. This person falls in love with another youth they meet in the past. They travel back and forth often between the present and the past.