As the daughter and granddaughter of racehorse trainers, Michelle Eustis had long hoped to train champions of her own.

But the 25-year-old Crete mother of one was killed and a friend was badly injured early Monday while riding a horse bareback together at Balmoral Park racetrack when her allegedly intoxicated fiance jumped into his truck to find them and sideswiped their horse, officials and family said.

Angus Lake, 41 — described as Eustis’ boyfriend by her father but as her fiance by prosecutors — is charged with four felony counts of driving under the influence. Lake, a horse trainer from Michigan, appeared in court via a video feed Tuesday, hanging his head as the charges were read.

After Assistant State’s Attorney Mary Fillipitch said Lake’s blood-alcohol level was 0.147, nearly twice the legal limit, a Will County judge set bail at $500,000. Lake has previous convictions for misdemeanor drunken driving and assault charges in Michigan and Ohio, the prosecutor said.

The three and several others were socializing in a Balmoral Park barn in Crete, after watching the Sunday night races, when Eustis and her friend Heather France, 21, decided to take Rendezvous — a horse that Eustis’ father, Chuck, trained — out for a late-night ride. Lake told state police that when the women didn’t return after about a half-hour, he got into his Dodge Ram to look for them.

Lake said he drove toward the women, riding on a paved road that circles the track, when the horse, an 8-year-old gelding that hadn’t recently raced, got startled and reared up. But Fillipitch said an accident reconstructionist determined that Lake, who told police he’d had as many as six shots, came up on the women too fast and tried to brake, sending the truck into a slide.

The truck then struck the horse, leaving a “”severe gouge”” in the animal and damaging the truck’s right side, Fillipitch said. Others, including the track’s general manager, Michael Belmonte, said the horse’s injuries were minor.

Public defender Kurt Leinweber said that while the incident was tragic, there was no evidence that Eustis was on the horse at the time or that Lake’s truck struck the horse. Eustis died of head injuries and trauma, according to the prosecutor and Cook County medical examiner’s office.

It was unclear Tuesday afternoon just how severely France, a self-employed horse groom, had been injured. Fillipitch said she suffered a broken leg and other injuries, which Eustis said also included a broken shoulder. He and others said France may have been left at least partially paralyzed by the accident.

Belmonte said Wednesday night’s races at Balmoral Park are scheduled to continue, but that the death of Eustis, whose family was well-known in Illinois harness racing, had stunned the racing community.

“”Ever since she was born, she’s always loved horses,”” said Chuck Eustis of his daughter. “”I’ve always had racehorses, and my father always had them. She started going to the track with us when she was 3 years old. In the summertime and after school, that’s all she ever wanted to do is be with the horses.

“”When she was done with school, she came to work with me. She can do everything. She can get them ready; she’ll bathe them, jog the horses. She gets them ready to race and takes care of them afterward.””

Two years ago, the Eustis family moved to Crete. Michelle Eustis lived with her parents and her 6-year-old daughter, Haylee. About a month ago, she began dating Lake, a longtime family acquaintance she knew through horseracing, her father said.

Her daughter is struggling to understand what happened.

“”We tried to explain that her mother went to heaven,”” Eustis said Tuesday. “”Before she fell asleep last night, she asked about Michelle. She hasn’t grasped the idea that she’s passed away.””

Eustis said he is struggling too.

“”I miss her dearly and I don’t know what to do,”” he said. “”It’s too early for her to die like this for no reason.””

Tribune reporter Andrew Wang contributed.