Kathleen Holey, 43, pleaded guilty to a reduced charge of attempted assisted suicide in August as part of a deal with prosecutors.
Holey's attorney pleaded for her release, arguing she has already served 182 days, but a prosecutor told the judge she should remain behind bars for at least a year.
Holey's son, Patrick Holey, died in the suicide pact but his wife, Jennifer, survived. Jennifer Holey has since been sent to prison on a no-contest plea in the rape of a 14-year-old girl.
Before sentencing, Kathleen Holey told Circuit Judge Randy Tahvonen that she tried to get help for the two 19-year-olds when they first discussed suicide. But she said she decided to help them end their lives because they thought they were facing life in prison in the rape investigation.
"That's when all of us lost our sense of thinking entirely," Kathleen Holey said. "All I can say is that I ask for mercy, and I am truly sorry."
She initially faced a charge of assisted suicide. Prosecutors said she supplied painkillers to the two and helped them find the abandoned Clinton County farmhouse where they tried to carry out their suicide pact on April 9.
At the time, the couple was being investigated in the rape case and state welfare workers had removed their infant daughter from their care.
Jennifer Holey now is serving a four- to 15-year sentence for her role in the rape of a minor. She gave birth to a second child in August.
Kathleen's sister-in-law, Mary Joetta Wendland, also pleaded guilty to attempted assisted suicide and was sentenced to six months in jail. She went with the group to the farmhouse and also provided drugs.
Clinton County Prosecutor Charles Sherman believes Kathleen Holey and Wendland are the first people to plead guilty to violating Michigan's four-year-old assisted suicide law, which was passed to stop Jack Kevorkian.
Kevorkian eventually was imprisoned on second-degree murder charges.
By Dee-Ann Durbin