Harvard professor Holly Prigerson said Annie had classic symptoms of a condition known as "prolonged grief disorder." Grief for a loved one can go on too long and become pathological, Prigerson said.
The risk factor is the attachment between the survivor and the deceased. "It's not how the person died," Prigerson said. "It's that sense of attachment and dependency; that I need this person to feel safe, secure, happy, whole."
Annie's friends said she talked about how much she missed her mother every day. But they had no idea how serious her mental suffering was.
"Hanging out with her, and being with her, you would never think that she was depressed," friend Rosey Kalayjian said. "She loved to laugh."
Kalayjian and other friends believe it was at night, when she was alone, that Annie's troubles would come back. "She would start thinking about everything again," friend Hillary Karmilowicz said. "And a lot of the images that she saw still came back to her."
Annie's friends said she had other worries, too -- problems with money and love. "I always say Annie, well, was like a little tortured soul," Kalayjian said.
"No matter how many flowers you buy her, no matter how many presents or fun nights out, deep down inside there is something nobody can fix."
As if memories weren't enough, there was also a TV movie of her mother's story, "Our Mother's Murder," continually reminding Annie of the past. "She used to get so depressed when it was on," sister Alex said. "So depressed, and she'd break down and go into tears and she'd turn it right off."
The movie aired again in mid-September. Alex said Annie mentioned that "mom's movie" was on again, but she's not sure if Annie watched it.
Two days later -- Sept. 24, 2009 -- seemed to start like any other day. After dropping her son off at school, Annie ran into a friend, beeping and waving as usual.
Then she met Alex. The two had lunch, followed by a pedicure and manicure. Then the two hung out at Annie's house until 6 p.m. "We were just laughing, you know -- talking about I have no clue what, but she was fine," Alex said.
About the time Alex was leaving, Annie sent friend Kalayjian a cheerful text message. Shortly after that, she got into her car and drove to the Tappan Zee Bridge. Police say Annie stopped her car in the middle of the bridge. She got out smoking a cigarette, and, at 7:50 p.m., she jumped. Her body was found in the river three days later.
Police found a pencil-written suicide note in her car. It begins with a goodbye to her 13-year-old son, Michael.
"My little Michael, my angel -- I loved you more than life," the note read. "I will love you forever. I tried to give you everything and will always be there. I'm so sorry I let you down. ... Alex and Alexa [Alex's daughter], I love you so much. Thank you for the smiles and for never giving up. ... Mommy and Daddy -- please find me!"
Alex said she cannot fathom what her sister was thinking when she jumped, especially after the "beautiful, fun day" the sisters spent together. "I have no clue what went through her head," Alex said. "No clue, and it's racking my mind."
Annie had made past suicide attempts, according to police records. But the haunting question remains: Why this way? Why the same way, the same place, as her stepfather so many years ago?
"I don't know," Alex said. "That's another thing that blows my mind."