To many people, religion is a big part of their life. At my church, they say that you should only date other Christians. I don't really believe too much in that, obviously since I dated this girl who was polytheistic. I don't remember what she was exactly, but she was like a druid and believed in all the nature gods and stuff, but that didn't affect our relationship. The only thing you have to think about is how big a deal her religion is in her life. She will definitely be pressured into either converting you or dumping you, so if she's really big in God it might be really difficult. Also, I dislike you calling religions cults. Although it is true in it's own way, a cult is generally deemed as a mass suicide ending. All religions that I know of are against suicide.