Valérie Trierweiler was taken to a Paris hospital after taking "one pill too many" the night before magazine claims of the affair between her partner, French president Francois Hollande and actress Julie Gayet hit the stands, a friend to the first lady said.
Last week, Trierweiler's staff said she was admitted at the Pitié-Salpêtrière Hospital, where Princess Diana died after a car crash in 1997, following a strong emotional shock.
The hospitalisation came after weekly tabloid Closer, printed photos purportedly showing Hollande and Gayet arriving separately at the same time at a flat not far from the Elysee presidential palace in Paris.
The first lady was initially due to be released after a couple of days but the length of her stay was extended six days.
At a press conference earlier this week, Hollande refused to disclose any information on her health, saying only she was "resting".
Le Canard Enchaine magazine reported Trierweiler had suffered a nervous breakdown.
However, according to a new account of the events published by Le Point magazine, pills were also involved.
"She just took one pill too many," a close friend of the first lady told the Paris-based weekly.
The source confirmed reports that Hollande confessed his love liaison with Gayet to Trierweiler as the two met at the Elysee palace the night before the scandal broke.
The 48-year-old journalist was said to be very drained by the confrontation, during which the president acted in a manner described as "cold and harsh", Le Point wrote.
Trierweiler then returned to her home and took some pills, waking up in the morning with a strong nausea.
"Her mobile phone was bombarded with requests [for comment], she felt lonely and on the edge of the abyss and asked to be hospitalised," Le Point reported.
The friend firmly rejected the possibility that Trierweiler intended to commit suicide.
Meanwhile Gayet has taken legal action for breach of privacy, against Closer.
The magazine told AFP that the actress is seeking 50,000 euros (£41,000) in damages and 4,000 euros in legal costs.