You cannot say " I have no heart to do sth." For example, Chicken soup for soul, not for hearts. : k O/ v; q! t% Y0 b8 dYour context is not very clear. So can you explain the contexts more clearly? 5 _" l5 l" y/ |9 ?Why you don't want to bother the boy again?
For the first context, just say I am sorry to bother you again. ! M) t! N G6 y g* K$ }6 Q0 JFor the second case, I don't think you can use hearts in this expression. You can say I am not meant to do sth...