be nothing to (one)
To be insignificant or unimportant to one. Projections are nothing to the CEO—he only wants to see our actual sales figures. We've been broken up for years—he's nothing to me now.
be/mean ˈnothing to somebody
(informal) not be important for somebody; not be a person that somebody loves: Why should he go to the funeral? The dead man was nothing to him.The danger meant nothing to them.