SACRAMENTO (AP) _ A 38-year-old woman convicted of taking her best friend's 12-year-old son as her lover has been sentenced to nine years in state prison.

Kathy Burman of Sacramento was sentenced Wednesday by Superior Court Judge Eugene Gualco, who called the case ''a tragedy for all concerned.''

A jury last month convicted Burman of seven child molestation charges. Prosecutors say the affair began in August 1990 and lasted for a year and four months.

Defense attorney Sherwin Edelberg said Burman was raped and terrorized into silence by the boy.

''I saw this boy on the witness stand,'' Edelberg said. ''He's as tough as nails.''

But Gualco said Burman's claim of rape was not believable in the face of evidence that she frequently signed the boy out of school, wrote him excuses and sent him at least one love letter.

''At the age this boy was, he was very impressionable when this woman took up with him,'' the judge said. ''She professed her love for him. He professed his love for her.

''There was no question that this was consentual, but as we know ... consent at this age is no defense to the crimes she committed,'' he said.

''She not only used him physically, but she played with his mind by these professions of love. Finally when the tryst comes to light, she plunges a knife in his heart by accusing him of rape,'' Gualco said.