Casper Smart is Jennifer Lopez's ''best friend''.

The 'On The Floor' hitmaker has been dating the 25-year-old backing dancer for over a year and credits him with supporting her through good times and bad.

Jennifer, 43, told the February edition of America's Harper's Bazaar: ''He's fantastic; he's like my best friend. I can tell him everything, when I'm feeling down, when I'm feeling good. He gives moral support, endless love and support.''

Although Jennifer admitted she isn't at her best when she is tired, the star - who has four-year-old twins Max and Emme with her former husband Marc Anthony- wouldn't change her hectic schedule for anything.

She said: ''The worst is when I'm tired. It's the overworking, which I've learned to say no to. I'm not my best self. I'm at my best, I think, when I'm giving love. I feel my best, I am my best, I need my best.

''I'm a singer. I'm a dancer. I'm a performer. I'm an actress. That's what I'm supposed to be doing. It makes me a better parent, a better person. I think I can just handle more than the average bear, you know?

''I make it as simple and as beautiful as I can because my life is kind of big. So I pack my luggage, or dress myself, or comb my kids' hair, pick up their clothes--that makes our life beautiful, you know? There's something very elegant in that.''

Jennifer is famous for her fashion choices and revealed she still has the palm-print Versace dress she memorably wore to the 2000 Grammy Awards.

She said: ''I have that at home. The other day, my housekeeper put it on a mannequin in my spa, where I get my hair and makeup done. She sent me a picture. She was like, 'You like this dress?' Um, yeah, but I don't know if I like it out in the house!''