well Hi I don't often post but thought I would reply to you.
She is in to a different religion/spirituality to you. The name doesn't matter, who the "leader" is doesn't matter the question is are the beliefs similar?
Does her belief system place an importance on the same things yours does
things like treat everyone kindly be nice to yourself be forgiving accept things you can't control the name of the belief system means nothing, don't be fooled by your thoughts on what she is following - seek first to understand where she is coming from. If her belief system is totally out of synch with the principles you live your life by then it is a biggy but if they are similar just using a different name then you don't have a problem.
One of the big lessons I learned through all of this is DON'T JUDGE based on gut feeling...your gut will tell you something is not right but that is a signal to explore and understand not judge!
People make mistakes. Life is a journey. She may have realised that you are the best thing to have happened to her and she made a mistake.
Let her know the words she needs to say to may u feel confident she is growing and changing. If she can't say them then perhaps she has not learned the stuff she needs to have learned in order to have a meaningful relationship with you
If not then it doesn't matter
Know your boundaries and give her the information she needs to know to understand how she can most effectively try to reconnect with you. Wicca/ Catholic / Protestant it does not matter as long as the core beliefs are consistent with you, don't get hung up on names / history etc.
