Girlfriend at Center of Gainesville Love Triangle Never Thought Killer Ex Was Capable of Murder

— -- The ex-girlfriend of Pedro Bravo, the Florida college student who was found guilty last week of killing her new love in the so-called Gainesville Love Triangle trial, said she never thought the smart, charismatic student she once dated was capable of murder.

“He kind of tricked us all, thinking, you know, this guy that’s shy and he wouldn’t hurt a fly,” Erika Friman told ABC’s Matt Gutman in an interview for “20/20.” “I don’t think anyone in their right mind would go as far as he has.”

Bravo, 20, was convicted of first-degree murder and six other counts in the death of 18-year-old University of Florida student Christian Aguilar. He was sentenced to life in prison.

Throughout the trial, prosecutors alleged that Bravo was so distraught over finding out his ex-girlfriend, Friman, was dating his friend, Aguilar, that he concocted a plan to kill him so he and Friman could be together again.

“This was a person we knew. This was intentional,” Friman said. “It makes it all so much worse. It’s like the knife just turns in your heart kind of thing.”

It came out during the trial that Bravo kept an incredibly detailed journal, in which he professed his love for Friman over and over again, writing obsessively about winning her back, and then, how he would get away with murdering the friend he had known since middle school -- all of which shocked Friman, who testified against Bravo and read the journal for the first time when she was on the stand.

“It sounds like the mind of a sociopath, or a sick person,” she said. “A lot of it was his obsession for me, and how he wanted me back and how he wanted to be with me.”

Friman said she started dating Bravo when the two were sophomores in high school in Miami. She remembered initially being drawn to him because he made her laugh, but by their senior year, he started to wear on her. She said she told him she wanted to take a break from their relationship, but Bravo wouldn’t accept it and appeared depressed.

“I felt like he almost manipulated me at that point in my life, where he was kind of like, ‘if we do these things, we’ll never be the same,’” she said. “I was really concerned that, I don’t know, something bad would happen if we took a break.”

So Friman kept dating him through summer 2012, until she had to leave for Santa Fe Community College in Gainesville, Florida. That’s when she said she told Bravo, “I don’t see a future with you, and I don’t want to do long distance, and this doesn't make me happy right now.”

“I tried to be as clear as I could, but I mean, apparently he didn't understand it,” she said.

When they broke up, Friman said Bravo was “very emotional” and cried, but she felt “free,” like a “weight had just been lifted.” After the break-up, she started seeing his friend Christian Aguilar, whom she said made her feel special.

“Christian made me really happy and we had so many things in common,” she said.

But after she arrived at college, Friman said she learned from a friend that Bravo had also enrolled at Santa Fe Community College and was still upset over losing her, even suicidal. Friman said she checked up on him, but kept her relationship with Aguilar a secret.

“I just felt like [Bravo] needed more time before hearing it,” she said. “When I spoke to [Bravo], I mean, I lied to him. I told him, ‘no [Aguilar and I are] not, we’re not dating, we’re just hanging out and I don’t know a lot of people here’... It was because I had already known he was suicidal and I didn’t want to throw him over the edge.”

Then, in September 2012, Friman said Bravo called Aguilar, saying he was feeling down and wanted help. Prosecutors claimed that Aguilar met up with Bravo and got into his car, where Bravo later poisoned him, strangled him with his belt, then dumped his body. Aguilar’s body was found 22 days later in a wooded area 60 miles outside of Gainesville.

Friman said she first realized Aguilar was missing hours after he went to meet Bravo when he wouldn't answer his phone. She started to panic and kept trying to call both of them until the early morning hours. Aguilar’s phone kept going to voicemail, but finally, Bravo picked up.

“[Bravo] answers and the first thing I ask him was like, ‘Where’s Christian?’” And he’s just like, ‘oh, you know, I was dropping him off, you know, we got into an argument, you know, a verbal argument,’” she said.

In police interrogation tapes played in court, Bravo admitted to police that he had met up with Aguilar on the night of his death, and the two got into an argument, but that Aguilar got out of the car and Bravo drove off without him.

When she couldn't find Aguilar, Friman made Bravo go with her to report him missing to police. She said she believed Bravo’s story that he and Aguilar had fought and Bravo had left him somewhere, but that Aguilar was hurt or lost. But as time went on, and Aguilar didn’t come home, she said her suspicion of Bravo grew.

“It was like nudging in the back of my head, Pedro must have been involved,” Friman continued. “It was sickening, almost, just because we knew him for so long, and Christian was his friend.”

Friman denied that being up front with Bravo about her relationship with Aguilar would have stopped Bravo from killing him, and doesn't regret testifying against him.

“People tell me all the time, ‘oh you’re so strong, you’re so brave,’ and I look at them, and I’m kind of just like, ‘well, if you were in my shoes, you would do the same thing, you would testify,’” she said. “If it was the love of your life you lost, and this is the one thing you can do for him, for his family, for his memory, you would find a way to pull it all together.”

Friman said there isn't a day that goes by that she doesn't think about Aguilar. She believes if he were alive today, they would have gotten married.

“I think we were soul mates,” she said. “You don’t expect to lose your love that young, and not in such a traumatic way… [but] at the end of the day, when I think of all these unknowns, I think of how much Christian loved me, and that’s kind of what gets my through it.”