MAZAR-I-SHARIF, Afghanistan » On the surface, the Gul sisters seemed to have it all: They were young, beautiful, educated and well off, testing the bounds of conservative Afghan traditions with fitted jeans, makeup and cellphones.

But Nabila Gul, 17, a bright and spunky high school student, pushed it too far. She fell in love.

Her older sister, Fareba, 25, alarmed at the potential shame and consequences of Nabila’s pursuit of a young man outside of family channels, tried to intervene. Their argument that November day ended in grief: side by side coffins, both girls dead within hours of each other after consuming rat poison stolen from their father’s grain closet.

Interviews with family members and government and hospital officials here reveal a tragedy of miscalculation: Under pressure from her older sister to halt communication with the boy, Nabila tried to eat just enough poison to scare her family but not kill herself. But she misjudged. Overwhelmed by guilt and grief, Fareba followed by taking her own life on the doorstep of the city’s most holy shrine.

The sisters’ deaths shattered their family and have struck a chilling chord for the residents of Mazar-i-Sharif, a city increasingly marked by the despair of its young women. For many, the deaths have come to symbolize a larger crisis: an intensifying wave of suicide attempts.

Although the government says it does not collect data on these cases, the city’s main hospital says it has been overwhelmed, with three or four such patients coming in every day, up from about one or two a month a decade ago.

The number of attempts has grown with such speed that the head of investigations for the police, Col. Salahudin Sultan, says he can no longer follow up on them.

"We don’t have the time or resources to investigate these," he explained. "We would hardly get anything else done."

As for the questions of why, and why here, there seem to be as many theories as there are cases. Most explanations focus on Mazar’s status in Afghanistan as an affluent cross-cultural hub, relatively more liberal and exposed to European influences. While Afghan girls here regularly are exposed to the social norms of the West through television serials and the Web, the fact is that they live in Afghanistan’s conservative and male-dominated society. The clash is cruel, and can be heartbreaking.

"Most of the girls don’t die, but they all take poison or at least threaten to kill themselves," said Dr. Khowaja Noor Mohammad, the head of internal medicine at Mazar-i-Sharif Regional Hospital. "This is their cry for help."

The doctor who tried to save the Gul sisters, Dr. Khaled, produced a patient ledger for the past two months. As he pored through the list, he uttered the names of several young women who had attempted suicide: Fatima, Mariam, Zulfiya, Zar Gul, Basbibi.

"There are probably 200 cases in here of attempted suicide," said Khaled, who goes by a single name, waving the ledger in the air. "In the last 12 hours, we had three."

Perhaps no case is more emblematic, or more discussed, than the deaths of the Gul sisters.

The two came from an educated, progressive family. Mohammed Gul, their father, is a prosecutor. Nabila was on the cusp of graduating from high school, and planned to attend college in the city. Fareba was already attending college and hoped to follow her father’s footsteps into the legal profession. The young women were determinedly modern, and would not have seemed out of place in many Western cities.

Nabila was impetuous, with a quick temper and a strong sense of self. She often challenged what Fareba told her, rejecting the deference held for elders in Afghan society. Fareba, a softhearted woman who often wept after small arguments, confided to a close friend that she felt Nabila did not respect her.

Their last fight, the morning of Nov. 26, involved a boy Nabila said she was in love with. Fareba thought the relationship was inappropriate, and urged her sister against it. Nabila refused, and the two began shouting.

Their mother heard the fight, and ran in to break it up, slapping Nabila twice across her face for talking back to her older sister, according to people close to the family. The younger girl ran off in tears.

An hour later, Nabila’s mother discovered her on the floor of her room, white foam dripping from the corners of her mouth.

At the hospital, doctors tried desperately to cleanse the rat poison from her system as family members surrounded the bed, begging Nabila to recover.

The mother shot an angry glance at Fareba and said: "If Nabila dies, it will be your fault," according to a doctor in the room at the time.

Mohammed Gul sat quietly, holding his daughter’s hand. She came in and out of consciousness. She said she had not meant to take so much poison, and that she regretted it now.

At 2:30 p.m., Nabila died. On the way home from the hospital, her father suffered a heart attack, and was admitted as a patient.

At the house, people began to gather. The Guls’ eldest son, Abdul Wahid, played host to the mourners who crowded into the pale green parlor of the house. But he was worried about Fareba, the sister he was closest to. She was not answering calls or texts.

At 4 p.m., his phone rang. It was Fareba. Her voice hoarse and slow, she said that she was at the Hazrat Ali shrine, a stunning mosque of cerulean tile in a sea of white marble. Stuck at the house with the visitors, Abdul Wahid asked his uncle, Malim Faiz Mohammad, to get her.

When he arrived at the mosque, Mohammad spotted a crowd near the entrance to the shrine. He found his niece lying on the cold marble in the center of the crowd. Strands of foam leaked from the corner of her mouth.

He rushed her to the hospital. Doctors put Fareba in a room down the hall from her father, who was still recovering. Neither knew the other was there.

No one else knew of Fareba’s whereabouts, either. With the family preoccupied preparing Nabila’s body for burial, the uncle said he decided then to keep the matter to himself, not wanting to upend an already fragile household.

The doctors worked on Fareba for more than an hour. Her uncle stood by silently as they performed the same procedure that had failed to revive her sister hours earlier. At 5:30 in the evening, the doctors pronounced Fareba dead.

"Dying this way just doesn’t make sense," Mohammad said in an interview. "I wish they would have died in an accident."

He took Fareba’s body back to the house, but hid it in a separate room off the side of the compound where no one would see it. He still could not bring himself to tell them the bad news.

The truth came out the next day.

Early the next morning, Mohammed Gul woke in the hospital. He sat for a while in the sun-washed room, gathering his belongings, still unable to grasp Nabila’s death. He needed to talk to Fareba about what happened, he thought.

Back home, he was escorted to the courtyard, where coffins sat side-by-side.

"Why are there two coffins?" he asked his brother. "Who is in the second one?"

The sisters are buried together in a nondescript graveyard a few miles from the family home, their graves marked with two wooden poles and a mound of stones. A band of Tajik children roam the cemetery, turning the muddy slopes into a playground.

Mohammed Gul rarely eats, and suffers continued bouts of sickness. His wife, devastated, rarely leaves their cold, concrete house. Reminders of the loss spring from everyday rituals like sitting down at the kitchen table, with two chairs now empty.

The parents seek comfort in small ways. At night, Gul and his wife sleep in the girls’ room, he on Fareba’s bed, his wife on Nabila’s. They have given away the sisters’ belongings, as is customary, except for a pair of dresses. On bad days, the parents clutch the clothing to their faces.

© 2013 The New York Times Company