Hayden Panettiere Splits From Hero Milo Ventimiglia

It appears the age difference finally caught up with Heroes co-stars Hayden Panettiere and Milo Ventimiglia who has reportedly split dues to “a lifestyle conflict.”

The two stars are believed to have ended their year-long romance last week but remain on friendly terms.

Pals say it was 18-year-old Hayden's love of partying that eventually proved to much for their relationship to handle.

A source tells Usmagazine.com, "It was a lifestyle conflict...(She) is young. She likes to go out in the Hollywood scene and that's not his style. (Ventimiglia) has been concentrating on work, on his production company."

At 31, Ventimiglia is 12 years older than the teenage actress.

Check out who Milo & Hayden will be joining on the sexy singles market below