The crash happened west of Paulina Avenue on the westbound side of I-290 just after 3 a.m.
ISP said the driver of a white Toyota sedan pulled it onto the right shoulder, with its hazard lights on. Three people got out of the Toyota to change a flat fire.
That's when 21-year-old Ashanti Gates, of Chicago, drove her black Hyundai Sonata into the Toyota and two people, ISP said.
The two victims, 18-year-old Erik C. Cox of Rolling Meadows and 18-year-old Shaelyn M. Sherwood of Hoffman Estates, were pronounced dead on the scene.
"He didn't deserve this. He had so much ahead of him," said Cox's girlfriend Lacey Puleo.
The third person from the Toyota was not struck.
A 4-year-old boy was among five people inside the Hyundai. Gates, the child and one other person from the Hyundai were taken to local hospitals.
Prosecutors say Gates was speeding, didn't have her headlights on, and had a blood alcohol concentration more than twice the legal limit.
Puleo said she and Cox had planned to attend Columbia College together, where he was planning to study graphic design. She said he produced music and had plans to create his own clothing line.
"We were going to do it all together. We were going to make it together. We were going to follow our dreams together, but she [expletive] took that away from him," she said.
A memorial is now growing in Kimball Hill Park in Rolling Meadows, where Cox and Sherwood often hung out, to the young lives lost.
"It wasn't supposed to end like this. He was supposed to get everything that he wanted and live a long life. He wanted to be a father. He wanted to get a dog," said Puleo said through tears.
Gates has been charged with two counts of Aggravated Driving Under the Influence of Alcohol, two counts of Reckless Homicide and Child Endangerment, ISP said on Tuesday.
A GoFundMe has been set up to support Cox's family, and has already raised $6,000.
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