I'll Be There For You by Louise Candlish
Hannah hugged her sister tightly. 'I know you don't trust life any more. But you've still got to live it - and so do I.'
Hannah and Juliet Goodwin have been best friends since childhood, but when Juliet's boyfriend Luke is killed just as Hannah marries the affluent Michael, the divide between the two sisters is suddenly too painful to bear. While Hannah prepares for the birth of her first child, Juliet begins to neglect her job, her health, and all those who love her the most. Hannah is the last person she'd appeal to for help.
But then she finds herself drawn into a secret betrayal that threatens to destroy Hannah's happiness before she even has a chance to enjoy it . . .