On Catholics Converting to Protestantism

I have a Reformed, Calvinist, Protestant background, and still reside within those circles. There are many former Roman Catholics there. And this brings me to how those Catholics became Protestants. Much in the Protestant belief system holds that Roman Catholicism is actually not a part of true Christianity, and it holds to at least a distorted gospel, if not a false one. Many therefore view Catholics as not true Christians, and they're all still dead in their sins.

In looking at these former Catholics turned Protestant, a pattern is evident. They aren't former Catholic true believers who have changed in their view of theology toward Protestantism. They are former unbelievers, who just happened to live their lives in a Catholic context. They were dead sinners with a hollow shell of religion that happened to be Catholicism. (Great numbers of Protestants fit this same description, I might add.) Their conversion wasn't to Protestantism, per se, but to life in Christ. It just so happens that those who had a great effect on their salvation were Protestants. Protestants who teach that Catholics aren't true believers. So these former Catholics now view themselves as having been unbelievers, not because they were simply unbelievers, but because they were Catholic. They explain their former sin in terms of what they now view as the false religion of Catholicism.

They are now zealous in trying to convert their family and friends to Christ, not realizing that some of them might be true believers who don't really have a reason to convert to Protestantism. Not sure if I got my point across here, but maybe I'll have a better mental day in the future.