#34: Kevin Costner and Christine Baumgartner

Duration of Relationship: 18 years (2004–2023)

The 2023 breakup between Kevin Costner and Christine Baumgartner ended their 18-year marriage, shocking fans who had long admired their relationship. Baumgartner filed for divorce, citing irreconcilable differences, with reports suggesting that lifestyle differences and Costner’s demanding work schedule had strained their marriage.

The split became contentious as the two navigated a legal battle over their three children’s prenuptial agreement and custody arrangements. Despite the public nature of their divorce, both Costner and Baumgartner remained focused on co-parenting.