Selena Gomez "always saw" ex-boyfriend Justin Bieber's potential.

Selena Gomez

Selena Gomez

The 23-year-old singer, who split from the Canadian heartthrob last October after four years of dating, is happy he is enjoying a career comeback with hits such as 'Where Are U Now' and 'What Do You Mean?,' and insists she never doubted his talent.

Asked about the 21-year-old star's success, the brunette beauty told the New York Times: "While people were writing that I was stupid for being in it [the relationship], this is what I always saw in him. I'm like, duh!"

The 'Good For You' hitmaker threw herself into recording her own upcoming album, 'Revival,' over the past year in a bid to cope with all of the attention on her personal life.

She said: "My public life was doing all the speaking for me, for a moment. I translated that into my music."

Selena admits she still has "trust issues" and wishes she could be more open like her best friend Taylor Swift, but likes being in control of her career after parting ways with her long-time manager, who is her mother Mandy, last year.

She said: "Taylor is a lot more trusting than I am. I have trust issues, given my situation. She's very open, so she brings out this other side of me.

"I definitely remind myself that I'm in control. I feel like ultimately if I sit down and I think about a decision I need to make, it's really within myself. I make the decision. Everything goes through me."