Lil:
You're preaching to the choir - I'm a Reformer, and hence have plenty of gripes with the RC, though not enough to withhold fellowship 
That having been said (very approximate dates to follow):
- from 33 - 65AD there was only a rather small sect that was called "the Way", later to be named "Christianity";
- between 65 - 400 AD it was growing and exploring its understanding of theology and struggling to keep agreeable;
- between 400 - 1000AD there was a unification into one denomination, with a few dissenters;
- between 1000 - 1600AD there were only two almost identical denominations and most of the main dissenters had folded;
- and since 1600 there was a failed attempt to reform the RC Church that led to schizm after schizm down to our day.
They evidently can't have been doing everything so wrong, if you hold to any concept of the Gospel being spread in a half-organised way (as did the Apostles).