Investigators believe he is armed and dangerous.
Several of Taylor's friends are currently worried about their own safety because Simon has not yet been arrested.
READ MORE: Woman killed on Christmas Eve remembered as selfless
"She's in a different place right now, and I just hope we find him," said Christine Izzo, one of Taylor's best friends. "We had bucket lists."
Izzo had lunch with Taylor on Christmas Eve, just hours before the 46-year-old was shot in front of her family and friends.
Izzo says Simon and Taylor had been dating for about six months and had a fight on Friday, Dec. 20, in Louisiana.
ORIGINAL STORY: Search for accused shooter continues after Christmas Eve killing
"Things seemed good, but when they were bad, they were really bad," Izzo recalled. "I don't know who could do something like this, you know, to somebody so kind...I know justice needs to be served."
Friends and family gathered on Friday at Cleveland Park for a vigil in honor of Taylor.
Meanwhile, federal and local authorities are still on the hunt for Simon.
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