According to TMZ, the two had an "acrimonious" breakup right before the Met Gala on May 2, which is sucky timing. The Met Gala should be fun, not a multi-hour event of internal seething and avoiding your ex.
Kylie was apparently less than pleased that Tyga showed up to the Met Gala following their split—she felt he was only invited because of her. Sort of like how you only know his name because of Kylie.
From the sounds of it, 26-year-old Tyga is already over the person who made him relatively famous. TMZ said that for Mother's Day, Tyga took his mom—and a lady friend—out to brunch. Scandal.
Tyga and Jenner have been together (except for a fall 2015 breakup) since mid-2014 when Kylie was a fresh-lipped 17-year-old. They apparently first met in 2011, when Tyga performed at Kendall's sweet sixteen.
There are no rumors yet as to why the couple broke up—nor is there any official confirmation from either party. Of course, eager spectators will likely be pointing the finger towards Blac Chya. Because drama, and Tyga's ex-fiancée/baby momma is becoming Mrs. Rob Kardashian.
The end of the Tyga-Kylie era is disappointing because it means there will be no half-siblings/cousins to Rob and Blac Chyna's baby to make the Kardashian-Jenner lineage even more confusing.