Kylie Jenner and rapper boyfriend Tyga are rumored to be "at each other's throats" and quarreling like never before, since she celebrated her 18th birthday.

A source tells Radar Online since then, Jenner's career has exploded and her life has become quite cluttered, prompting family and friends to fear that the once enamored pair's relationship may soon be a distant memory.

"Kylie and Tyga have been bickering nonstop lately," said a source. "It is to the point where it is almost annoying to be around them because they create such an awkward situation."

The two were recently spied leaving older sister Kendall's Westwood apartment together. They looked as if they'd rather be other places and perhaps with other people. In addition, Kylie recently took to Snapchat to describe her 25-year-old boyfriend as "mean."

Word is, Tyga has taken exception with the way his girlfriend's career has been going of late and has warned her that she may be overexposing herself.

"He just wants her to slow down and enjoy her life without working all day, every single day," said a source. "But Kylie does not want Tyga's advice any more when it comes to her career and tells him to worry about his own career and stop trying to meddle in hers."

In addition to all that, Kylie has continued to feud with Blac Chyna, Tyga's ex and the mother of his young son King Cairo. She recently talked about how she often feels bullied by the older Chyna, and how it often leaves her feeling wounded and in tears.

But now it seems she has more to worry about and deal with where her boyfriend is concerned.

"Unfortunately, if things keep going the way that they are between Kylie and Tyga, they will be done in no time," said a source.