Ben Affleck is happy to evenly divide his fortune with Jennifer Garner.

The Oscar winner, who confirmed his split from the actress last week after 10 years of marriage, reportedly isn't worried that she is legally entitled to half of his $75 million net worth.

A source told OK! magazine: ''They don't have a prenup, and Ben knows he's the one who screwed up the marriage. Jen's the mother of his three kids, so he's fine with letting her take half.''

The 'Butter' actress - who is rumoured to be worth $60 million in her own right - is said to have reached her breaking point after rumours began swirling the 42-year-old actor was cheating on her and gambling excessively behind her back.

The insider said: ''True or not, that sent Jen over the edge. They'd gone to counselling, and she'd tried to forgive his behaviour, but enough was enough. She became exhausted by the innuendo that followed them everywhere.''

The duo started ironing out the terms of their split on June 20 over lunch with Jennifer's mother.

An eyewitness said: ''Ben looked miserable. He leaned back, crossed his arms and ordered nothing but water.

''Jen's having a hard time, but she can't live like this anymore. Ultimately, this was her decision.''