India, Feb. 5 -- Justin and Hailey Bieber are headed for a $300 million divorce, with sources claiming that their union is "hanging by a thread," as Hailey struggles to cope with her husband's alleged immature behaviour and substance use while they raise their infant son, Jack Blues.

Right now, Hailey's "main concern is her son". She is allegedly determined to protect her child's well-being, even if that means distancing herself from Justin. This could involve pursuing a share of his estimated $300 million fortune and seeking full custody of their five-month-old son.

National Enquirer reported that Justin is deeply troubled over the possibility of being called to testify in the upcoming sex trafficking trial of his former mentor, Sean '...