Selena Gomez is "relieved" Justin Bieber is apparently seeing Kourtney Kardashian.

Selena Gomez

Selena Gomez

The 23-year-old beauty - who is also said to be dating One Direction hunk Niall Horan - is glad that her ex-boyfriend has found romance with the reality TV star because she no longer has to feel guilty about the fact her love-life has moved on.

A source told the Hollywood Reporter: "Selena was under the impression that there was no one serious in Justin's life. At least that's what he told her. So when Selena and Niall took their friendship to the next level, she actually felt concerned with how Justin would take the news.

"Now that she knows about Kourtney, she doesn't feel bad for Justin one bit. She's more relieved than ever that she's moved on with such a great guy."

Meanwhile, it seems things are hotting up between her and her 22-year-old new flame.

Niall joked about marrying Selena during a Carpool Karaoke segment on 'The Late Late Show' earlier this week, during a game of "sleep with, marry, cruise" on the show presented by James Corden.

Asked to choose between Demi Lovato, Selena and Tina Fey, Niall replied: "Sleep with Tina Fey. Let's marry Gomez and go on a cruise with Demi Lovato. Great voice, we could be singing songs."