SPRING HILL — Inga Marie Swanson could be generous and kind.

Every Wednesday, she would bring candy for members of her Bible study group. On Sundays, she would donate little plastic bags of pocket change. She could be funny and witty. Compassionate. Bubbly.

But she could also be quiet and reserved, shutting herself in her room, studying the Bible and quietly listening to Christian radio. Her boyfriend said she could be so shy she would exit the room when a stranger entered. She was modest and dressed conservatively.

The way friends and loved ones remember Marie, as many knew her, presents a complex and at times contradictory picture.

But one thing is clear.

The events leading to her death this month took those around her by surprise and have generated a long list of unanswered questions.

How did such a modest, compassionate and devout woman end up standing naked that Saturday afternoon in front of two off-duty law enforcement officers with a firearm?

• • •

The details of the shooting are still murky.

Hernando County sheriff's Detective Rocky Howard, 31, and Tampa police Officer William Mechler, 26, were attending a gathering of a couple of families on Oct. 20 at 9070 Orchard Way.

The home belongs to Howard's in-laws. He lives nearby.

Swanson, naked and acting irrationally, approached the group uninvited, according to the Hernando County Sheriff's Office. She left, returning a short time later with a firearm, according to the Sheriff's Office.

Authorities have not identified what type of firearm she was carrying, but Swanson's live-in boyfriend, David Simpson, said it was an antique firearm that had been mounted on the second floor of his home. It had belonged to his father.

He said that the single-shooter had no bullets and that the barrel had to be held in place by hand or it would fold downward and the barrel would aim at the ground.

"She would have to have a finger under the barrel to keep it up," Simpson said.

When Swanson returned to the property about 1:20 p.m., authorities say, she confronted the deputy and officer with the firearm, and the two law enforcement officers fired, killing her.

The story gets a little more unusual.

Earlier that afternoon, two men had seen Swanson walking around naked and carrying a large silver cross. She approached them later, waving the cross and making statements about an "Antichrist." They never called authorities.

The Florida Department of Law Enforcement is investigating the incident but has declined to provide any specifics.

Authorities have not disclosed how many times the officers fired or whether Swanson aimed the firearm at the officers or any other people. They have not disclosed whether anyone called for on-duty assistance after Swanson first appeared naked and irrational.

• • •

Swanson, 42, moved to Tampa from Connecticut with her family in 1979, her brother said.

As a teenager, she attended Gaither High School.

Her family eventually left the state, but she never did. Always independent, she started working and living on her own when she was 17 or 18, paying for her own apartment and car.

She worked for many years as a waiter, bouncing around the Tampa Bay area, living in Tampa, Pasco and Hernando. She went for her associate's degree but never graduated, said former boyfriend David Mull, who met her in the early 1990s.

Several years ago, they moved to Hernando and lived, as friends, in a small mobile home near where she met her last boyfriend, David Simpson.

• • •

Swanson never had a job in the three years they were together, Simpson said. He didn't think she had worked for years before they met in 2009.

She tended a neighbor's horses and did odd jobs around the house.

Mostly, she studied the Bible.

"Any time you went in the room, she was always in the Bible," Simpson said. "All the time."

The pages of her Bible are worn and crinkled, the edges smudged. The margins swell with notations in neat capital letters. "PEOPLE AND PLACES IMPORTANT," she wrote in the Book of Nehemiah. Hardly a page is free of her careful underlining or highlighting.

She filled pages with passages she had printed from memory.

Swanson was sweet. Wonderful, in Simpson's eyes. Different.

She had her issues.

"She believed she was coming to an end, I believe," Simpson said. "She always told me she was going home. She always told me she was dying of cancer."

Gunnar Swanson said his younger sister was never diagnosed with a mental illness.

He couldn't say what happened. He called her a sympathetic and understanding person.

"It was almost like she took their pain on as her own," he said.

Pastor David Brockhoff of the Holy Trinity Lutheran Church in Masaryktown said Swanson was kind, frequently giving him little cards of encouragement that always included a prayer.

"She had a very sensitive personality," Brockhoff said of Swanson, who attended his church regularly, though was not an official member. "She would really either express a lot of joy or show that she was struggling with something."

• • •

Nobody yet has an answer to the question on everyone's mind:

How did this happen?

"No one would have seen a break with reality like that," Brockhoff said. "Clearly, something big happened."

Her brother couldn't imagine how his sister came to be carrying a weapon. Or nude. She always wore long sleeves and pants — even socks with sandals.

No one suspected heavy drugs or alcohol were involved.

Swanson occasionally smoked marijuana and took over-the-counter sleeping medicine, but that was it, Simpson said.

But Simpson did notice a change in his girlfriend in the few days leading up to the Oct. 20 incident.

She had become worried about some political differences and discussion of some church members' financial problems at Bible study the previous weeks, Simpson said.

"She was different. Totally different," he said. "She kept saying, 'My brain won't shut off.' "

She had difficulty sleeping and would wake up to scribble lines from the Bible.

"I could just tell it in her eyes," he said. "She wasn't the Marie — the Boo Boo — I knew."

She told Simpson that everything would be back to normal after the Nov. 6 election. He was concerned but didn't think it was that serious.

• • •

Simpson left for work that Saturday at 6:45 a.m.

She was awake. He told her she should go back to bed.

He gave her a hug and kissed her goodbye.

"I'll be back," he said.

"Okay," she said.

And he left for the day.

Danny Valentine can be reached at dvalentine@tampabay.com or (352) 848-1432. Reach him on Twitter @HernandoTimes.