Personally, I could care less what other people believe as long as their hearts are in the right place.
It seems obvious that you and your girlfriend have a strong friendship.
As He said, "I have come that they may have life, and that they may have it more abundantly" (John ).
Bottom line: before taking another step forward in this relationship, we'd advise you and your girlfriend to get some expert advice from an objective third party. Have a serious conversation about how you envision your life together and how you will deal with life's issues.
I soon lost touch with the church when my teenage years hit and I left school.
I returned to religion in my 20s, spending some time reading the bible, attending the Alpha course and generally seeking spiritual fulfilment.