State police say a semi truck traveling in the opposite direction crossed the median Friday about 5 p.m., and slammed head on into the woman's SUV.
The front of the semi sustained heavy damage but its driver Donald Campbell was not seriously hurt. The 36-year-old man from Valparaiso, Ind., was cited with improper lane usage late Saturday.
The victim of the accident was identified as 49-year-old Mary Lacy.
"Everybody liked her. She was a really nice person. And she's going to be so missed. So missed. She touched so many lives," said the victim's sister, Susan Lacy.
The Lynwood resident lived with her siblings.
"When my folks died four years ago, I moved in with her and my disabled brother. And I'm on disability, too, and she's basically provided a home for us for the last four years," Susan Lacy said.
The accident happened as Mary Lacy was headed home in her Ford Explorer from her job. Relatives say she worked for 20 years as a typist for the Social Security Administration.
"A lot of people relied on her. They'd give her work when nobody else could do it or when there was overflow. And she always stepped up and did it with a good attitude," Susan Lacy said.
Mary Lacy enjoyed cooking shows, science fiction and her cats. She was also active in her faith.
"We were very involved with a group called Via de Cristo. We'd go on Christian retreats and that, and we were actually getting ready for a weekend in November, being part of a team," Susan Lacy said.
At least two other vehicles were involved in the accident but no one else was seriously injured.
Illinois State Police say they continue to investigate.