HOUSTON, Texas (KTRK) -- In just seconds of walking into a Shell station, Shane Coyle knew he wanted to date Donna Pena.
"I walked in and I saw this smile," Coyle said.
Six months later, he asked Pena to marry him.
"I was trying to save money for the ring so I could do it properly," said Coyle, Pena's fiancé.
The 31-year-old mother of two was working to make extra money as she switched careers from a medical assistant to go to welding school.
"This world was better with her," said Coyle. "It's worse without her."
"I'll never have her call me again, text me again, nothing," Pena's best friend, Sandra Moyer, said. "She's all I had."
Pena was working at the Shell location on FM 1960 and Perry Road when she was fatally shot during a suspected robbery Friday night.
Coyle says he talked with her less than an hour before that.
"All I know is, she was held hostage, and then shot after she gave them money," said Coyle.
The search is on for those responsible as her friends and family wrestle with why someone who was there to take money also had to take her life.
"I want them caught for the sake of the next mother that's sitting there trying to pay her bills working at a Shell station or anywhere," said Moyer.
Pena's family has set up a GoFundMe to help pay for funeral arrangements.
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Fiancé mourns loss of clerk fatally shot during gas station robbery in NW Harris Co.