People claim that the 64-year-old has quickly moved on since both he and Kris, 58, filed for divorce last month.
“Kris is devastated,” a source told the publication.
“This was her former assistant and best friend of 20 years.
“Kendall and Kylie grew up with her two kids and have been their best friends. She's so sad and completely heartbroken.”
Bruce was first pictured out with Ronha at an Elton John concert in LA earlier this month.
Kris and Bruce announced their separation last year and said they remained close friends but that may not be the case for much longer.
Neither Kris nor Bruce have commented on the reports yet.
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