Fort Hood soldier Vanessa Guillén, 20, disappeared on April 22, 2020, and was later found murdered
juan cruz and vanessa Guillen
Juan Cruz and Vanessa Guillen

The weekend before 20-year-old Fort Hood soldier Vanessa Guillén disappeared last April, she spent much of her time with her fiancé Juan Cruz and family in Houston.

"Every time she came, it was a like a honeymoon to me," says Juan, 22. "Everything was perfect."

The couple had gotten engaged a month earlier, and they were both looking forward to a December wedding.

"She had the planners, everything," says Juan. "She had the wedding hall, the band, to what type of food."

After the weekend, Vanessa returned Monday morning to Fort Hood, where she was a small-arms mechanic with the 3rd Cavalry Regiment.

juan cruz
Juan Cruz
| Credit: Octavia Jones

Two days later, Juan says he exchanged texts with Vanessa in the morning — but then she abruptly stopped responding.

"I was thinking, 'What's going on? What happened?,'" says Juan. "I was confused. This is not her."

She didn't respond to texts or calls from her family either.

For more than two months, Vanessa's family and Juan searched for answers. During that time, her family alleged that Vanessa had previously told them that she had been a victim of sexual harassment at the hands of others in the military.

Then, on June 30, their greatest fears were realized.

Sixty-nine days after she vanished from Fort Hood, Vanessa's body was found along the Leon River near Belton, Tx. She had been murdered and then mutilated.

The main suspect, Army Specialist Aaron Robinson, killed himself when confronted by police just hours after her remains were found. Authorities arrested his girlfriend Cecily Aguilar who is accused of helping to cover up Vanessa's murder and dispose of her body.

She has pleaded not guilty. A trial date has yet to be set.

vanessa guillen
Vanessa Guillen
| Credit: US Army

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Juan and Vanessa's family are still waiting for answers.

"I just want to know what happened," says Juan. "Every day I pray for justice."

While they wait, Vanessa's family and their attorney, Natalie Khawam, are pushing for change in the military and are calling for federal legislation: The I Am Vanessa Guillén Act would create a new system for reporting and investigating sexual harassment and assault in the military, putting trained professionals outside an accuser's chain of command in charge. It would also change the way the military handles missing persons cases and give sexual assault survivors who are service members the right to make civil claims against the military. Currently, service members have no such recourse.

"The system is broken," says Khawam, founder of the Whistleblower Law Firm. "These soldiers don't have rights. They don't have voices. And when they speak up, they get retaliated against."

For more on how Vanessa Guillén's fiancé and her family are honoring her memory, subscribe now to PEOPLE or pick up this week's issue, on newsstands Friday.

vanessa guillen march
Vanessa Guillen March
| Credit: Carolyn Caster/AP/Shutterstock

In addition, the family plans to start a foundation named after Vanessa that would bring awareness to sexual harassment and assault in the military, and would help provide services for service members affected.

"We don't want what happened to my sister to happen to any other military member ever again," says Vanessa's sister Mayra. "I think this story is more than enough to show that there needs to be change in the way that we handle the sexual harassment and assault and I feel like it's our responsibility now to help those that need it."

Juan, who plans to be involved in the foundation, says Vanessa's legacy will live on through the proposed bill and the foundation.

"She is my hero," he says. "Because of her, a lot of people are speaking up. And I know she's proud. She will always be remembered. That's what she wanted, to help people."