FORT LAUDERDALE, Fla. -- She was a married mom living in suburbia. Her youngest child no longer was home because he joined the Army just like his dad did decades earlier. Yvonne Serrano had uprooted her life as a military wife time and time again. She thought she could change her life a bit by joining a close-knit gym community.

To some acquaintances, she came across as intense, abrasive and self-absorbed -- far from the nurturing, supportive members of a Coral Springs gym called "Fit Bodies Forever-Training for Warriors."

Serrano was a loner who didn't seem to fit in, they say. It only got worse one drunken night at a bar, police say.

When the opportunity arose to attend one of the monthly outings of gym members, Serrano, whose own membership had been suspended, was on board.

It was supposed to be a fun outing -- a movie and drinks. But instead of mingling and making friends, the 51-year-old spiraled out of control, growing agitated, more intense and intoxicated as the night went on, according to gym members who were some of the last to see 21-year-old gym member Daniela Tabares alive.

"It was bad energy," Carolina Miller said.

Miller said that up until that November outing, she had never set eyes on Serrano. The first impression was awful: "Aggressive. It wasn't fun. She was grabbing guys. She had a lot to drink."

Coral Springs police say Tabares stepped in and offered to drive a drunken Serrano to her home from World of Beer on Nov. 23, and at some point Serrano shot Tabares in the forehead.

A few hours later, police found Tabares in Serrano's driveway. The driver's side door of the young woman's Nissan Kicks was ajar. One foot remained inside the car.

To some at the gym, it's as if the November outing is on a reel playing over and over in their heads three months after Tabares was shot. Did something out of the ordinary happen? Did the women exchange words? Could anyone have foreseen this? Stopped it?

Who was this woman, a loner, who was so unfamiliar to this group?

Serrano was born in Panama. She met Douglas Serrano when he was stationed there. They married in 1993 and moved to the United States a year later, traveling the country and making their homes at various military installations as their family grew.

Home was Miami; Kansas City, Mo; Panama City, Panama; Corpus Christi, Texas; Washington, D.C.; and Tracey, Calif., according to court documents.

In 2006, the same year Serrano's high-ranking husband retired from the military after 28 years, she received her massage therapist license from the state of Florida. Two years later, they moved to Coral Springs and remained in the same home, finally achieving a sense of stability.

Until Nov. 23, at no time was Serrano on anyone's radar for problems with drugs, mental health issues or crimes. She has no known health issues. She has a small collection of guns.

Court records say Serrano, who is one year short of completing a civil engineering degree, had never been in trouble with the law. Serrano's passion, records say, was physical fitness and wellness.

Training for Warriors should have been a natural fit. Those who stick with the program say it's not like most gyms where people work out in isolation. A goal of the those behind the program is to build camaraderie among students by motivating them and making them feel empowered enough to encourage one another to keep pushing, to get stronger, to be their best.

Tabares, many say, embodied that. She became a regular while working and going to college. She made many friends there. She cared deeply about making people feel comfortable.

Serrano, who attended predawn classes, was not among Tabares' friends.

Many of those friends, like Miller, decided to attend the November outing of a movie and drinks.

Miller remembers arriving at the Promenade at Coconut Creek and asking who the stranger was in their row of seats at the movie theater.

It was Serrano. She works out at the gym before dawn, gym friends told her.

Miller took her seat, as did others. After the credits rolled for "21 Bridges," the 10 or so in the group walked over to World of Beer.

At World of Beer, Serrano sat outside by herself and tried to get Tabares to join her. She didn't, eventually setting Serrano off.

Miller said Serrano stormed into the bar and blurted: "What the (expletive) is wrong with you? I was waiting outside."

Miller said she tried to distance herself from Serrano the rest of the evening, but Serrano was hard to ignore.

At one point Miller said she saw Serrano holding three drinks at a time. She said she also watched Serrano grab a young man as he approached Tabares.

Serrano made others uncomfortable as well, Miller said.

"She was intense," said gym member Andrea Kammarada. "It was this intense vibe and I just remember thinking, 'Did I do something?'"

Sometime after midnight, Miller decided to call it a night, leaving the bar and Tabares behind. Now, she, a 46-year-old woman who considered herself to be Tabares' gym mom and close friend, has a hard time forgiving herself.

"I tried to take care of her the best I could," Miller said. "I did what I could. I guess I wasn't paying attention to what was going on ... . so I left."

The following morning Miller got a call from Isa Tabares asking where her daughter was.

"I never thought for a second something like this would happen," Miller said, crying.

Police also called Miller the morning after the outing, telling her they needed to speak with her. "I kept asking where Daniela was and, 'Why are you calling me?'"

She said she went to Serrano's house in the Maplewood neighborhood of Coral Springs, but police had roped off the area to onlookers.

In a five-minute telephone conversation with an emergency dispatcher, Serrano repeatedly says she doesn't know how the body ended up in her driveway.

"What's going on there?" the dispatcher asks just before 6 a.m.

"I don't know," Serrano begins. "I don't know. I just walked out and there is a car in my driveway with a dead body."

"With what?" an apparently jolted emergency dispatcher asks.

"A dead body," Serrano says.

"A dead body?" the dispatcher repeats.

The dispatcher asks Serrano how she knows the person is dead and whether she knows the person.

Serrano is silent.

Serrano tells the police she walked out of her house on the way to the gym when she saw the car and body in her driveway. Police note in their report that Serrano was not dressed for the gym.

Serrano tells another cop the same story about heading to the gym and coming across the gruesome discovery, but then she adds more, saying she was at World of Beer with friends and blacked out. She said she woke up in her bed.

Police searched the car for clues and reported they found 9 mm Lugar shell casing in the passenger seat floorboard of Tabares' car.

Police say they went inside Serrano's home and saw Serrano touching a damp tank top in the laundry room. The police report says they asked her about it and she tells them she was wearing it the night before but washed it when she woke up.

It is at this point, detectives claim in their report, that they prepared to get a search warrant.

Serrano's story -- with the exception of not remembering leaving World of Beer -- changes again.

This time she tells them she woke up in the car and how the driver's side door was open. She explains how she saw Tabares hanging out of the car in the driveway. She says she walked around the front of the car and crouched down placing her hand on Tabares' chest to see if she was breathing.

She wasn't.

So she grabbed her purse and headed inside, pulling out her 9 mm Sig Sauer pistol that she had brought out with her the night before. She said she placed the pistol in between some pillows in her bedroom and then she peeled off her lace tank top and washed it.

She told police, records say, that she went onto her Ring doorbell app on her phone and deleted the files. Whatever footage that may have been collected on her phone, does appear to be gone.

Serrano then called 911: "There's a car in my driveway with a dead body," she begins.

Serrano was arrested and booked in jail in Broward County. She's been there since, held without bond, which is customary for those accused of murder.

That could all change.

Weeks after her arrest on murder and tampering with evidence charges, prosecutors opted to file a lesser charge of manslaughter.

Serrano has pleaded not guilty to the lesser charge: manslaughter with a firearm, which carries a maximum 30-year sentence. The lesser charge also may allow Serrano to bail out of jail while awaiting trial. A hearing on setting bail is set for Wednesday.

Isa Taberas said she struggles to find the right words to describe her anger and frustration at the possibility that bond may be set low enough for Serrano to get out of jail.

She said her will to stay alive at the moment is only because she wants to see justice for her daughter.

Miller, while trying to be supportive and strong for Tabares' mother, said she's knows the hard truth. "At the end of the day, it's not going to bring her back."