The Weeknd broke up with Selena Gomez and not vice versa (Details, pics)

The Weeknd is the one who ended his relationship with Selena Gomez -- not vice versa according to reports and it had nothing to do with Justin Bieber ... TMZ has learned.

Multiple sources connected to The Weeknd and Selena tell said, their relationship had been fizzling out since Summer. They had rarely seen each other because of his touring schedule and her shooting schedule. They started talking less frequently on the phone.

We're told Abel enjoyed being single before he met Selena and felt unfairly tied down in a relationship that had lost its passion. Sources also said several weeks ago Abel called Selena, explained how the relationship was no longer working for him and then ended it.

The source say the two still remains friendly and have even talked several times since the breakup.

As for Justin Bieber... we're told he was not a factor in the breakup. Justin's apparent reignited relationship with Selena didn't start until after she and The Weeknd went their separate ways.

As for Abel... he's not sulking. He's a quick rebounder.