A man convicted of fatally stabbing his ex-girlfriend’s daughter in Dutchess County last May was sentenced Monday to serve life in prison without parole. 

Almost one year has gone by since 29-year-old Melanie Chianese was viciously stabbed to death by her mother’s ex-boyfriend.

On Monday, her killer, Paul Senecal, seemed to cry and apologized in Dutchess County Court before he was sentenced for first-degree murder. 

MORE: Dutchess County man convicted of murdering daughter of his ex-girlfriend

“You slaughtered Melanie and you slaughtered her mother’s heart," said Judge Edward McLaughlin.

Chianese’s mother, Cheryl, was there and said in an emotional victim’s impact statement that she never wants to hear Senecal’s name again. 

“I watched the defendant brutally stab my daughter on my Ring camera as she ran for her life covering the wound to her neck," said Chianese  

Prosecutors say Melanie was killed last May at the Wappingers Falls home she shared with her mother and 3-year-old son while Senecal was out on bail and wearing an ankle monitor for seven separate domestic violence offenses against Cheryl. 

“He became angry and wanted revenge for being rejected. His obsession with Cheryl escalated. He threatened her and he threatened Melanie who he blamed for Cheryl’s rejection," said Senior Dutchess County Assistant District Attorney Lindsey Richards.

Senecal blamed the devil for the murder at trial and his attorney said Monday that he’s mentally ill – even though the Dutchess County man was found competent by three experts. 

Prosecutors also said Senecal repeatedly broke a restraining order after his arrest last spring by contacting the victim’s mother by phone, mail and email while behind bars. 

Cheryl Chianese was granted a 99-year restraining order as a result and the judge put it on record that Senecal should have restricted means to communicate during his life sentence.

Chianese now has custody of Melanie’s son who has autism and just turned 4-year-old. She said her daughter was killed before her dream could come true to hear her son say “mom.”