Her roommate, Beau Zabel, was murdered steps from their South Philadelphia house last month.

Whose composure could survive that?

Zabel was shot to death returning from his job at Starbucks by a killer who stole his iPod. There's been no arrest.

Surely, Guerreiro would flee to family and safety in her hometown of Bethlehem? Surely, she'd reconsider her plan to teach in the Philadelphia School District?

"Everybody has been asking me why I'm still here - my parents, my family," Guerreiro said.

She tells them this: The tragedy has steeled her determination to stay put and live out the dream she shared with Zabel: to teach inner-city kids.

She has even kept Zabel's school supplies to use in her classroom in the fall.

Guerreiro also has joined with a national organization to raise awareness about crime and trauma victims, by sponsoring a runner in the Marine Corps Marathon in October.

The runner who will race in Zabel's memory never knew him, but he's connected in a profound way.

He's Andrew Shanks - Guerreiro's new roommate.

He's moving into Zabel's old room this weekend, and he has inherited the furniture Zabel's family left behind.

When Guerreiro asked Shanks if he'd run in honor of Zabel in the marathon, he immediately said yes.

Zabel was "the best roommate I could ask for," said Guerreiro. He was "super-clean and responsible. Living with him made me feel safe."

The two met on roommates. com and moved into the rental house on Ellsworth Street near 9th in May, shortly after Zabel moved here from Minnesota to teach math.

Guerreiro, 22, graduated from Temple with a degree in education in May and decided to stay here to teach.

"We were both going through it together, interviewing, picking out our outfits, getting our resumes together," she said.

"I don't have my family here. It was nice to know he was in the same position I was. I never felt like I was alone."

Guerreiro was visiting family in Bethlehem on June 15, when Zabel was murdered. She rushed back.

"It was surreal. I didn't know what to think or do. I got in my car and I just drove to Philly and I just sat in my house.

"I got boxes and got ready to pack up his things. His mom came down from Minnesota. She could only take a couple of boxes on the plane.

"I packed up the rest and donated it to Philadelphia Aids Thrift. I kept a few things out of his room.

"I told his mom I'm using his books, his pencils, his pencil sharpener, his ruler, everything that I could, in my classroom, so at least a part of him is there."

A few days after Zabel's murder, Guerreiro read an outraged op-ed about it in the Inquirer written by Kathleen O'Hara.

O'Hara, whose son was murdered in 1999, is a board member of Witness Justice, a national nonprofit organization that helps survivors of violence and trauma.

For the second time this year, the organization will sponsor a group of runners called Team Heal Trauma to race in the Marine Corps Marathon on Oct. 26, in honor of crime victims.

Guerreiro got in touch with O'Hara after the article ran, and they talked about finding someone to honor Zabel in the race this year.

The runner pays $88 to register and commits to raising $500 in sponsorship funds for the organization.

"I used to be a runner, but not a marathon runner," Guerreiro said.

But she knew that Shanks, her new roommate, already had run two triathalons and was preparing to run a third.

She asked if he'd do it.

He said he'd always wanted to run the Marine Corps Marathon.

And now he'll do it for Beau Zabel.

"I just feel I owe it to him somehow," said Shanks, 24, who moved from Virginia Beach to Philadelphia a month ago to work as a customer-service rep for the Flyers.

"He left a bunch of stuff and it's things I needed and didn't bring: a bed, a TV, all this other random stuff.

"Running in this marathon - it's my way to honor him and thank him."

Said Guerreiro:

"What happened is so horrible, but some good things are slowly coming out of this.

"And that's what Beau would have wanted." *

A benefit will be held from 4-6 p.m. on Aug. 3 at the Starbucks where Beau Zabel worked, at 4th and South streets, to raise money to sponsor Shanks in the marathon. Contact Kathleen O'Hara at keohara@aol.com.

E-mail porterj@phillynews.com or call 215-854-5850. For recent columns:

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