Los Angeles, Feb 17 (IANS): Oscar-winning star Charlize Theron says she started "making out" with herself and her dolls when she was seven.

She said: "I was making out with myself at seven, I made out with dolls and with myself in the mirror."

During her appearance at "The Ellen DeGeneres Show", the 43-year-old star, who has denied the rumours linking her to actor Brad Pitt, also joked that her childhood antics explains why she is currently single, reports femalefirst.com.

Theron, who has two adopted children, Jackson and August, said: "It's why I'm single."

Despite being one of the most in-demand actresses in Hollywood, Theron had previously admitted she is convinced she will get "fired" from every movie she works on.

"I still have this every single time I start a job, 'I'm going get fired. They are going find out I'm a terrible actor. This is going be the one. This is going be the job where they all find out I'm just a total lie'."