TRUE Christianity is between man and God and has nothing to do with the Catholic Church. The church cannot save anyone, annalex. I get tired of Catholics thinking they are the one true and only church that God created. It isn’t. He created the one true church, the Body of Christ, and all believers, Catholic or not, are part of it. I know you don’t believe that but ...
Of course I don't -- neither history, reason or scripture say so, unless you mean the Catholic Church and the Orthodox Church, and maybe some pre-Chalcedon ones. The communities of faith that emerged from the Reformation are in deep contradiction with the scripture and can lead one away from salvation just as easily as toward it, especially with the indifferentist sentiment that you expressed.