Courtesy of Jillian Manuel

A makeshift memorial was set up near the site where Mollie Judith Olgin, 19, and Kristene Chapa, 18, were shot in a nature reserve in Portland, Tex.

The lone survivor of a shooting that left her girlfriend dead in a South Texas park says she has learned that “life is so fragile” and she thanks those who are praying for her, noting it has sped up her recovery, in some of the first comments posted to her Facebook page since the attack three months ago.

Kristene Chapa, 18, was shot in the head along with her girlfriend, Mollie Judith Olgin, 19, on June 22 in Portland, Tex. The couple had been spending some time in a nature reserve near Corpus Christi before going to see a movie on the night they were attacked, Olgin’s father, Mario, told local television station kiiitv.com.

A couple found the pair the next day in the park. Olgin, a first-year university student living in Corpus Christi, died; Chapa, of Sinton, was alive and rushed to an area hospital.

"Today marks 3 months since my accident. I've learned life is so fragile and cherish the people you have in your life love them don't take things for granted and buy pepper spray! they deserve it!" Chapa penned Sunday in a Facebook post.

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"I love that people pray for me," she also noted. "I really think that's why I'm recovering so fast."

Police got 100 leads in the case after Chapa, who is recovering in a rehabilitation facility, helped them produce a sketch of the attacker, NBC local affiliate, kristv.com reported in mid-September. The suspect is described as a thin white man with a scruffy beard, in his 20s, weighing 140 pounds and standing 5-feet-8-inches tall.

On her Facebook page, Chapa complained about the food at rehabilitation but also said of therapy: "one step at a time" and "always remember there is someone worse off."

A state forensics lab in Austin will compare DNA evidence collected from the crime scene with mouth swabs that police have taken from each person they’ve interviewed who doesn’t have an alibi, kristv.com reported.

But the lab is dealing with a lengthy caseload, and it’s not clear when police will have the results, according to the television station.

Police recovered a bullet casing from a large-caliber gun at the scene, leading investigators to believe the shootings occurred where the pair was found. Two witnesses said they heard what could have been gunshots or firecrackers just before midnight on June 22 but did not report it at the time.

On Sunday, Chapa posted the lyrics to a Kenny Chesney song on her Facebook page from "Who You'd Be Today," which is about a person who "died too young."

"I still need time but I am happy," she wrote. "I'm moving on."

That seemed to include a new girlfriend, with Chapa noting in early September that she was in a relationship with a new woman.

"I know people deal with things different and I'm not gonna sit in my room and cry over what happened," she wrote. "I was heartbroken but I'm not gonna be single for the rest of my life ... she's in my heart but I needed something else. I wanted a girl to be there for me and understand what I'm going through ..."

Portland Police Chief Randy Wright has previously said that there was no evidence to indicate the attacks were motivated by the couple’s relationship. Calls placed by NBC News early Monday seeking comment to Wright and Hilario Chapa, Kristene’s brother, were not immediately returned.

Courtesy of Hilario Chapa

Siblings Patricia Martinez, left, Hilario Chapa, and Mary Kristene Chapa on April 28, 2012. Kristene Chapa is recovering from being shot in the head on June 22 in a South Texas park. Her girlfriend, who was also shot in the head, died in the attack.

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Courtesy of Jillian Manuel

Rainbow ribbons, messages, flowers and cut-out hearts were left near the site in Portland, Tex., where a couple found Mollie Judith Olgin, 19, and Mary Kristene Chapa, 18, after they were shot.

Friends and family of two teenage girls in a same-sex relationship who were shot in the head in a South Texas park expressed shock and grief Tuesday over the incident in which one of the young women was killed and the other severely injured.

Mollie Judith Olgin, 19, and Mary Kristene Chapa, 18, were found in knee-deep grass in a nature area in Portland by a couple Saturday morning, said Portland Police Chief Randy Wright, who confirmed to msnbc.com details first reported by the Corpus Christi Caller Times.

Rainbow ribbons, goodbye messages, flowers and cut-out hearts were posted around the site where they were found. On Friday, a candlelight vigil and walk will be held for Chapa and Olgin.

“It’s something that I think all of us are going to carry with us for a while,” Frank Reyna, a friend of both girls, told msnbc.com. “It’s going to take a while to get past this, the idea that there is somebody still out there that did this to these two amazing, beautiful people, and that they’re walking free right now.”

Olgin, originally from Ingleside but recently living in Corpus Christi, died; Chapa, of Sinton, was rushed to an area hospital where she was in stable condition, Wright said Tuesday in a statement.

Wright said police had recovered a bullet casing from a large-caliber gun at the scene -- leading investigators to believe the shootings occurred where the pair was found -- but they haven’t found the weapon. Two witnesses said they heard what could have been gunshots or firecrackers just before midnight last Friday but did not report it, he said.

“If we had a name, you know, we’d be having a different conversation right now. But we have not been able to gather enough information to identify a suspect yet,” Wright told msnbc.com on Monday. “It appears as if … this was not just a random attack but that’s something that we really have to develop over time.”

Courtesy of Jillian Manuel

A makeshift memorial was set up near the site in Portland, Tex., where a couple found Mollie Judith Olgin, 19, and Mary Kristene Chapa, 18, after they were shot last week.

A motive had not been established, he said in the statement.

"Information from family and friends indicates that Mollie and Mary were engaged in a same-sex relationship. However, there is no current evidence to indicate the attacks were motivated by that relationship," he said.

Teen lesbian couple found shot in Texas park

Chandler Nunez, who noted that Olgin was one of her best friends in high school, said she was in shock.

“ … I cannot imagine anyone who would want to hurt such a loving and caring person,” she wrote to msnbc.com. “This was incredibly unexpected and the lack of answers makes this tragedy all the more frustrating.”

Friends said the pair had been together since mid-February.

Reyna, a 19-year-old university student, said he grew up with Chapa, and met Olgin his sophomore year of high school. He described Chapa as an athlete who played softball, and said Olgin, a student at a nearby university, was focused on academics but also was a big joker. He last saw them together at a local coffee shop in May, which was the first time he saw them out as a couple.

“I’m glad that that was the last time that I saw Mollie in person, that that’s the memory that I can live with for the rest of my life, knowing that I saw her happy,” he said.

The couple’s relationship “was a readily accepted thing,” he added, and was not what their friends focused on.

“We focused on their personalities and how they got along with everybody else … their kindheartedness and their ability to just make other people smile and make each other smile,” he said. “We didn’t care … what they were, it’s who they were.”

Wright said Monday that all indications were that “third parties” were involved in the assault. Because of her medical condition, Chapa has not been formally interviewed about what happened, he said.

The park, more of a nature area with some parts overgrown and no lights, was often frequented by visitors during the day, but not at night. It is located along a bluff overlooking a bay, Wright said, with some homes situated nearby.

“We’re not really sure how they got to the point that they were found,” he said. “It is a scenic overlook with a wooden deck and there is a place at the edge of the deck where you can actually go down a very steep incline into a grassy area that leads down to the shoreline, and that’s where they were found.”

The crime rate is low in Portland, north of Corpus Christi on the Gulf of Mexico, Wright said. The last homicide occurred two years ago.

Courtesy of Kristen Veit

Charlene Camp, Hilary Avila, Myracle Taylor, Bailey Sanders, Jillian Manuel, Tim Robinson (behind Manuel), Kristen Veit, LuAnn Garza, Valerie Tanon and Franceska Hiracheta were some of the couple's friends and well-wishers who created a memorial at the site around where the young women were found in Portland, Tex., last week after they were shot.

While people in the South Texas community prepare for their memorial service, another candlelight vigil for the pair has been organized by Cleve Jones, a gay civil rights activist who conceived the AIDS Memorial Quilt, for Wednesday evening in San Francisco. On Facebook, people noted they would hold vigils in other cities, too.

"You were taken too soon," Megan Olgin, who identified herself as Olgin’s sister on Facebook, wrote in a post. "I love you and always will. You're my guardian angel. I love you little sister. Forever and always ♥"

Editor's note: The Portland Police had initially spelled Chapa's name as Christine, though her friends spelled it Kristene. The police department's latest press release Tuesday evening has changed the spelling to Kristene.

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