Kartheiser and Bledel had met on the set of Mad Men but waited until filming was over before dating.
They are parents to four-year-old son Rhys and 6-month-old daughter Willie.
Brin filed for divorce from Shanahan in January 2022 citing irreconcilable differences.
Billionaire Elon Musk reportedly got down on one knee and begged Google co-founder Sergey Brin for forgiveness after Musk’s alleged affair with Brin’s wife Nicole Shanahan at a swank art festival in Miami Beach late last year.
The creator of the hit sitcom The Big Bang Theory, Chuck Lorre has filed for divorce from his wife Arielle Lorre, 36, marking the end of his third marriage.
It comes just over a month after they celebrated their third wedding anniversary.