Before it was... it was never about you having magic. [Only that you kept it from him. In that sense, yes, he feels betrayed - even now.]
... I never doubt that you're loyal to me. That you... care for me. [He might have his issues surrounding that, but he doesn't doubt it.]
I trust that you'd never truly harm me. I know that. [After what they'd gone through, before he died, he could never truly think that. And that's his point. That whatever's happening could cause them unintentional troubles.]