WAUKEGAN, Ill. (AP) _ A woman who disappeared after being accused of killing her lover 21 years ago, only to be found earlier this year, was sentenced Friday to one to three years in prison for manslaughter.

''It's all over now, except for her to do her time,'' Assistant State's Attorney Joe Collina said after Bernice Van Heise, 63, was sentenced by Lake County Circuit Judge Harry Hartel Jr.

Ms. Van Heise will be eligible for parole in nine months, the Lake County prosecutor's office said.

Ms. Van Heise, who lived quietly for years as wife and mother Gretta Knickerbocker, said she had mixed feelings about the guilty plea she entered last month in the Jan. 31, 1968, shooting death of Eugene Douglas.

''I did it for all my children in their new lives,'' she told reporters in this county seat nearly 25 miles north of Chicago. ''I didn't want them dragged through this thing.''

Prosecutors agreed to drop murder charges in exchange for Ms. Van Heise's guilty plea.

''We didn't pursue murder charges because some of the evidence was old and some of the memories were beginning to fade,'' Collina said.

In 1968, Douglas and Ms. Van Heise had been having an affair for about a year, prosecutors said. Douglas, a 48-year-old Glenview artist, was shot when he told his lover he was leaving her to return to his wife and children, prosecutors said.

''She claimed that the shooting was an accident and that she was handing the gun to Douglas when it discharged and he was shot,'' Assistant State's Attorney Michael Waller said Friday. ''Strangely, he was shot in the back of the head.''

Douglas' widow, Pat Douglas, and her two daughters were in court for the sentencing. ''There's no way that anybody's going to make up for what happened,'' she said. ''But I'm very happy it's been taken care of.''

Shortly after Douglas' death, a judge rejected the filing of a murder charge on the basis of insufficient evidence.

A grand jury later indicted Ms. Van Heise on murder charges, but she had disappeared. The indictment was withdrawn in 1975.

Investigators took up the case again after a friend of Ms. Van Hiese's daughter was overheard discussing the case.

Ms. Van Heise was re-indicted in February after authorities located her in the rural town of Elburn, about 40 miles west of Chicago. She and her husband of 20 years, Conrad Knickerbocker, had moved there in 1976 from the Chicago suburb of Hinsdale.