Mary Lou (Copelli) Hamacher passed away on October 3, 2018 at Brookdale Assisted Living Facility. She was born in New Derry PA on April 10, 1943.The daughter of the late Comillo “Pat” and Katie (McInchak) Copelli. Mary Lou retired after 45 years working for Saint-Gobain and/or predecessors. Mary Lou was always willing to step up and help or volunteer for any worthy cause. Nearest and dearest to her was her Parish Church, St. Martin’s in New Derry. Mary Lou volunteered as Parish secretary for 46 + years. She served as lector, Chairperson of the Parish Finance Committee, Secretary of the Rosary Altar Society for many years, and President of the Rosary Altar Society since 2009. In addition to St. Martin’s, Mary Lou donated her time to the DCCW. She was awarded, the Bishop Brandt Medal of Honor. She served for 8 years as Treasurer of the DCCW. Mary Lou was a member of the Second Class of the Latrobe Leadership Program sponsored by Latrobe Area Chamber of Commerce where she also was an active board member of the Chamber for several years. She was on the Board of The United Way of Westmoreland County. She was Treasurer of the Derry Lions Club. She was Campaign Manager for PAKCO Industrial Ceramics for the United Way. She received the Saint-Gobain Volunteer Recognition Award. Mary Lou served on the Board of the Christian Community Counseling Center. Mary Lou was Chairperson of the Supervisory Committee for the PAKCO Employees Federal Credit Union. Mary Lou was part of the first women’s leadership of the United Way of Westmoreland County. They were responsible for organizing the Faith in Action Program. Mary Lou was an Active part of PATH (Partners advocating Total Health) at Excela Health. In addition to her parents, Mary Lou was predeceased in death by her loving husband Ronald “Ron” Hamacher who she was married to for 49 years; an infant sister Catherine; two brothers, John “Scale” and Steve “Skeeze” Copelli, four brothers in law, Alderigo “Borg” Novello; Richard, William and Hubert Hamacher. Two sisters in law, Rose and Martha Copelli, and in laws Anthony and Ann Hamacher. Mary Lou is survived by daughter, Luann (Jack) Murtha, Son, Ron (Tracy) Hamacher; Her “boys”, her “Pride and Joy”, grandchildren,Tyler Leitza (Emily McIntosh), Lucas Leitza (fiance Courtney Funk), Derek Hamacher (fiance Kenzie Varrato), Dylan and Damon Hamacher; and 3 step grandchildren, Jessica, Patrick and Alec Murtha; sister, Christina (Teanie) Novello and brother Andrew “Gus” (Pat) Copelli; along with many loving nieces, nephews and friends. The family will receive friends for Mary Lou’s Life Celebration, on Thursday, October 4, 2018 from 6-8PM and Friday, October 5, 2018 from 2-4 and 6-8PM at the Matthew X. Merlin Funeral Home Inc. 529 N. Chestnut St. Derry, PA 724-694-8331. St. Martin Rosary Altar Society will recite the Rosary 2PM Friday, October 5, 2018 in the funeral home. A Mass of Christian Burial will be held 10:00AM Saturday October 6, 2018 in the St. Martin Roman Catholic Church, New Derry with the Rev. Salvatore R. Lamendola as celebrant. Interment will follow in the St. Martin Cemetery, New Derry. In lieu of flowers, Mary Lou requested that contributions be made to the St. Martin Rosary Altar Society c/o Linda Newell 125 S. Ligonier St. Derry PA 15627. Online condolences may be made to the www.merlinfuneralhome.com.