A girl runs away to live in a house in a cemetery. Two friends come over and they make a suicide pact. I picked out this chapter book from the library for a report in 4th grade (~1984), made a shoe box diorama of three girls sitting cross legged. Creepy!
“Runs away to house in the cemetery” evokes Jean Karl’s Beloved Benjamin is Waiting, but I do not recall the other friends and a suicide pact from it. Copies of BBIW are rare.