SAN ANTONIO – The relationship started when Erin Castro was 16 — a young, impressionable girl with dreams and ambitions.
It ended when on her 19th birthday, after she was murdered by a man her family said should never have been in her life.
Castro's older sister, Ashley Rios, laid out a history that reveals a teenage girl drowning in a world of insecurity and abuse.
Castro had a loving family, a passion for animals and a painful secret.
Rios remembers when Castro began changing.
"It started with bringing her down, her insecurities. 'You're gaining weight.' (He was) just calling her ugly names on the phone," she said.
Rios said Castro's boyfriend, Josh Garcia, poked at insecurities that already plague today's teenage girls.
"She believed him, and I feel like that's what happens to all these young girls. Weight is a big deal for these girls — and makeup. Erin actually didn't start wearing makeup until after they were dating," Rios said.
Through it all, Castro kept up her school work and seemed OK. Rios had no idea her sister was in danger until the first attack happened.
"She was starting to push away from him. She said they went driving around and he had gotten upset. (He) parked the car, started wailing on her," Rios said, showing a picture of Castro in a wheelchair at the hospital after the attack.
Garcia was convicted of aggravated assault and given two years' probation.
Castro cut contact for a long time.
"He made his way back in her life. She had hid it from all of us. She said, 'He's changed,'" Rios said.
By the time Rios found out, the verbal abuse had returned.
"I was scared for her," Rios said. "But instead of blowing up on her — because you know when you tell a teenager 'you can't talk to him' or 'you can't be friends with him,' what are they going to do? Do it behind your back — I wanted her to know it was OK to tell me. She was strong."
Castro was strong enough to do the scariest thing -- leave.
"She was, like, 'I want to go to school.' Her mind was set that she was done," Rios said.
On Sept. 3, Garcia wanted to talk. It was like deja vu in his car again. He was angry; she was done.
Garcia's arrest affidavit said he stabbed Erin, then ran her over with his car so she wouldn't call police. He was charged with murder and remains in the Bexar County Jail on a $200,000 bond.
Since then, Rios has learned from the National Resource Center on Domestic Violence that, every year, about 1.5 million high school students nationwide experience physical abuse from a dating partner.
Three out of four parents have never talked to their children about domestic violence.
"If you're hurting, whether it's emotionally or physically, I think you should just come out and say it. Say it to anything. 'OK, now I've said it to my stuffed animal or my pet. Now let me try and say it to somebody else,'" Rios said.
Rios said time matters. The longer abusive relationships go on, the more dangerous they become. She wants young survivors to know that control, violence and fear are not love.
Anyone who is suffering abuse or knows someone who needs help can find a list of resources at www.ksat.com/domesticviolence.
EDITOR'S NOTE: Following this article’s publication, Courtney said viewers’ comments have helped her identify other stories and angles that she plans to explore in upcoming stories for this series. She reflected on this process in a video that later aired on KSAT’s News at 9. You can find the News at 9 — and all of KSAT’s newscasts and local programming — on your favorite streaming device.