This complicated relationship is about to get even messier.

Shortly after Selena Gomez was spotted kissing The Weeknd, the “Starboy”s singer’s ex-girlfriend Bella Hadid made her feelings on the situation known by unfollowing her one-time friend Sel.

MUST SEE: Check Out Our Predictions for Selena and The Weeknd’s Relationship!

And now things are about to get even more complicated as In Touch has learned that the new couple has been secretly seeing each other for more than a year.

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Bella, the source says, “is going to be livid when she finds out Selena has been secretly dating The Weeknd for a year!”

Of course, this is particularly problematic — considering The Weeknd (real name — Abel Tesfaye) was with Bella for much of the past year before ultimately calling it quits in November.

“Their relationship deteriorated as they started spending more and more time apart due to work commitments,” the source tells In Touch exclusively. “She began to lose trust when his calls and texts became less frequent. In the back of her mind, she had her suspicions that there was someone else, but little did she know that person [was] Selena!”

MORE: Kylie Jenner Spotted Partying With The Weeknd — What Will Bella Think!?

This isn’t the first time Sel has crossed the Hadid sisters; in August, Selena’s ex Justin Bieber accused her of cheating with Gigi Hadid’s beau, Zayn Mali — but Gigi was willing to look past that (as they were closely affiliated through Taylor Swift’s squad).

“Gigi wanted to give her the benefit of the doubt,” the source tells In Touch. “But since learning that Selena’s been hooking up with her sister’s ex, she’s dropped her. Gigi refuses to answer Selena’s calls.”

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Gigi and Selena.

Of course, the former Disney Channel star has been openly flaunting her relationship and doesn’t have any problems with the drama she caused — and it would appear Bella is trying her hardest not to let it get to her, either.

“Bella believes [Selena’s] a drama queen who likes to stir up trouble,” the source adds.

For more on this, pick up the latest issue of In Touch — and for more exclusive content sign up for our newsletter!

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