Family, friends and fans have flooded Rihanna and A$AP Rocky with well-wishes over their pregnancy news — but not everyone is jumping for joy.A source tells OK! that their baby joy is a sore spot for the singer's ex-boyfriend Drake. “His ego has been badly bruised,” the source dishes. Drake, 35, who dated Rihanna, 33, on and off for several years before splitting for good in 2016, “hasn’t been able to get her out of his head.""He's bitter because he doesn’t get why she’s with a guy like Rocky," the source spills.A$AP, 33 — who’s been romantically linked to Rita Ora, Iggy Azalea and Kendall Jenner — “is well known to have a major roving eye and serious skeletons in his closet,” adds the insider. After the Fenty founder debuted her baby bump in a series of loved-up shots with A$AP last month, Drake promptly took to Instagram with a cryptic post about “shallow souls,” which friends saw as a dig at the couple.IT'S ONLY 'A MATTER OF TIME' BEFORE A$AP ROCKY PROPOSES TO RIHANNA, 'HE CAN'T IMAGINE HIS LIFE WITHOUT HER,' SOURCE SPILLSDrake "thinks Rocky is unworthy of Rihanna,” the insider dishes. "He thinks Rihanna made a huge mistake by not sticking with him. Rihanna wishes Drake no harm, but it’s sad for her that he can’t move on and let her be happy.”As OK! reported, the Fenty Beauty founder first revealed the exciting baby news with a glimpse at growing belly during a romantic stroll with her man in New York City last month.Despite Drake's sourness over his ex's news, other celebrities couldn't help but gush over the baby announcement, as OK! previously reported.Lizzo, 33, was among those who took to social media to offer the pair her congratulations, writing: "IM SO HAPPY FOR RIH N ROCKY CONGRATULATIONS AHHHHHH."RIHANNA SHOWS OFF GROWING BABY BUMP DAYS AFTER GOING PUBLIC WITH PREGNANCY NEWSKhloé Kardashian — who shares 3-year-old daughter True with Tristan Thompson — commented on a photo of Rihanna's pregnancy belly, writing: "This makes me so happy."Paris Hilton also tagged Rihanna in an Instagram post, which read: "Congratulations Queen! So happy for you @badgirlriri. You look so beautiful and are going to be an amazing mother. Celebrating you and @asaprocky and your precious baby on the way."Rihanna's father, Ronald Fenty, also dished on his daughter's announcement, insisting she is "going to be a good mom," as OK! learned.