The Oscar-winning star lost her mother Darnell Hudson Donerson, 57, brother Jason Hudson, 29, and seven-year-old nephew Julian King in a grisly shooting spree in October 2008.
Admitting the grisly incident was like a "blur", the 28-year-old star went into seclusion following the family tragedy.
The singer-and-actress revealed to VH1 documentary `Behind the Music`, that she was in shock for a long time, saying: "It was like I was outside of myself."
As the reality of what had happened hit home Jennifer fell into depression.
She said: "For almost two weeks straight... [I was] inside one room with just family and friends coming in and out."
William Balfour, Jennifer`s sister Julia`s estranged husband, has been charged with first degree murder and home invasion in connection with the killings and has pleaded not guilty to all the charges.
Jennifer also opened up about how becoming a mother has helped her come to terms with her loss.
She said that `Little David` - her 11-month old son with fiance David Otunga - "reminds me of my nephew" and he also helps her remember her mother.
She explained: "In so many ways I channel her because she was such a great mom. I want him to get the same love and the same upbringing my mother gave us."
Oprah Winfrey has been named the world`s most powerful celebrity.
The TV star - who fronts `The Oprah Winfrey Show` and is the president of media company Harpo Productions - has topped the annual Most Powerful Celebrity poll conducted by Forbes magazine, knocking Angelina Jolie off the top spot with earnings of $315 million last year.
The 56-year-old star was previously named top of the coveted list in 2007 and 2008, before Angelina - who is now in 18th position - took over from her in 2009.
The 2010 figures also include a number of new stars, with Lady Gaga flying into fourth place with earnings of $62 million, behind Beyonce Knowles with $87 million in second, and film director James Cameron in third with $210 million earned last year.
The Forbes Most Powerful Celebrity list looks at wealth, TV/radio popularity, press rank, web rank and social status - with even twitter followers being taken into consideration.
The 2010 poll placed `Twilight` star Robert Pattinson on the list for the first time, in 50th position following the success of the vampire movies, and after earning $17 million last year.
His co-star and rumoured girlfriend Kristen Stewart came 66th after earning $12 million from the franchise and working on new movie `The Runaways`.
Despite a tumultuous year in her personal life, Oscar-winning actress Sandra Bullock was placed eighth in the poll after pocketing $56 million in the past 12 months. She was just behind golfer Tiger Woods, who was placed fifth, Britney Spears, sixth, and rock band U2 - consisting of Bono, The Edge, Adam Clayton and Larry Mullen Jr. - who were placed seventh.