LAWRENCE – A Lynn man about to go on trial in Lawrence Superior Court for stalking, threatening and assaulting his former girlfriend opted instead to confess and received three to five years in state prison with probation.Jury selection was under way for Victor Matias, 43, last known address of 72 Warren St., third floor, when he decided to confess, pleading guilty to a string of charges Thursday afternoon that included breaking and entering with intent to commit a misdemeanor, assault on an occupant, four counts of assault and battery as well as stalking, two counts of intimidation of a witness, two counts of unauthorized use of a motor vehicle, two counts of threats to commit a crime of assault and battery with a dangerous weapon and a single count of violation of a restraining order before Judge Timothy Q. Feeley.In addition to the committed term of incarceration, Matias will be on probation for another five years when he is released from prison, at which time he is to stay away from his accusers, complete a batterers program, be evaluated for substance abuse treatment and counseling and abide by all court orders. He also will be on a GPS tracking device for 30 months during his probationary term.Assistant District Attorney Marsha H. Slingerland stated she was prepared to establish at trial that the incidents covered a time span from April 2009 until Nov. 16, 2009, involving a series of episodes in Beverly and Lynn.Matias was in a relationship with his former girlfriend for about 11 years and they have four children.When their relationship unfolded, Matias began showing up at her Beverly apartment and assaulted her on April 25. He stalked her, stole the keys to her car and showed up at areas in Beverly where she was with her children. He then entered her home, without authorization, on Oct. 22, struck her and stole the keys to her car.Then on Nov. 14, Matias made several threatening calls to her sister’s home on Hawthorne Street in Lynn, where she was visiting at the time.Slingerland read a letter from his former girlfriend in which she told of the impact the ordeal has had on her and her children.Slingerland said her recommendation of three to five years took into account the case and the suspect’s record.Defense lawyer John Benzan urged the court to be lenient, proposing a jail term instead of a state prison sentence, pointing out to Feeley that no one was seriously injured.But Feeley felt the prosecutor’s punishment was more appropriate and imposed the punishment sought by prosecutors.