Michelle Williams is reportedly worried about "repeating the same mistakes" she made with Heath Ledger now she is dating Jason Segel.

The actress split from late actor Heath Ledger several months before he died of an accidental overdose in 2008.

Reports surfaced at the end of last month that the blonde beauty has become romantically involved with her long-time friend Jason. Sources say the relationship came after years of soul-searching for the star.

"Michelle told one friend, 'I love him!'," a source told US Weekly, who added that the star "had a lot to recover from" as she mourned the death of Heath.

Michelle, who has six-year-old daughter with Heath, was deeply affected by her sudden loss. His death impacted the 31-year-old star. "[It] took a huge toll on her. She is a romantic and always felt partly responsible for not being able to help Heath," the insider added.

"She doesn't want to repeat the same mistakes she made with Heath."

However, sources say Michelle's worries are unfounded. Jason has reportedly promised his new girlfriend a fresh start.

"Jason has already shown her his commitment to her," an insider revealed.