Hi Mortemir,
Well I happen to think it's okay to marry somebody how does not have their minds open to this truth... IF they they are not steeped in religion/Christianity and are totally accepting of how you believe. I think waiting for a believer that you feel is right for you, is unlikely to say the least. And marriage to a unbeliever can work, it does for me.
Where your children are concerned, you are responsible for instructing them about the gospel of Christ... they really need to know the Bible stories and names of the people and it's good to start at an early age. Now parents can use the many books available that are on a child's level to teach them.
But I just could not go to a church to be instructed and preached at and interact with the people and listen to their conversation about their beliefs... as their understand is so dramatically different from what I/we believe. I mean how would you hold your tongue and not debate with them constantly? And what good would that do anyway, but create a confrontational and adversarial atmosphere every time you were there. I think it's the thing you cannot mix the new with the old.
Luke 5:37 And no one puts new wine into old wineskins; or else the new wine will burst the wineskins and be spilled, and the wineskins will be ruined.
I would not want and don't think I could be a part of a church that I disagreed with so completely on what they teach. And they would not want me there either... debating would eventually get you kicked out.
Now an option you might consider, if your girlfriend is insistent that children need to go to church. When they are school age just take them to Sunday school, drop them off and pick them up. Actually this is what my own parents did, they were not church goers at the time, so they took us to Sunday school. I know that is not ideal, but some churches have very active children department classes, where they can learn a lot about the Bible stories and enjoy the activities and you would have minimal contact with it. Of course you could/should certainly give your children further instruction at home. It's not a ideal solution, certainly would not be right for everybody, but maybe for some where a parent really desires the children to be churched, it is an options.
Anyway just wanted to give you my thoughts.
mercy, peace and love
Kat