Yes, it's the victim's obligation to retreat in Massachusetts.
Even if a blood-soaked naked maniac holding his erect penis in one hand and a chainsaw in the other is pursuing you with the intent to hack you and your family into fish bait, it's the home owner's duty in most of New England to flee their dwelling -- potentially leaving a family member behind to a grisly end.
"Section 8A. In the prosecution of a person who is an occupant of a dwelling charged with killing or injuring one who was unlawfully in said dwelling, it shall be a defense that the occupant was in his dwelling at the time of the offense and that he acted in the reasonable belief that the person unlawfully in said dwelling was about to inflict great bodily injury or death upon said occupant or upon another person lawfully in said dwelling, and that said occupant used reasonable means to defend himself or such other person lawfully in said dwelling. There shall be no duty on said occupant to retreat from such person unlawfully in said dwelling."