Firstly, I'm not a committed christian neither am I married, but if I were both:

I would not divorce him, even though I know it will be hard on the relationship. There is a possibility that it can work, but if the said husband becomes hostile then there will surely be problems and stress in the marriage. If he decides to let me and the kids carry on as usual, then I don't see there being any problems.

With regard to fellow christians, I don't think I will be making a broadcast for advice because I feel that any decision I make would be down to myself, taking the children into consideration.

With regard to being an unmarried christian, I don't think I would married someone who is not a christian because there will be too many problems. But I suppose it would depend on how deeply I am involved in the said religion.

The fact that the wife is a christian, then they should continue to stand on the what the bible states.
Mark 10: 2Some Pharisees came up to Jesus, testing Him, and began to question Him whether it was lawful for a man to divorce a wife. 3 And He answered and said to them, “What did Moses command you?” 4 They said, “Moses permitted a man TO WRITE A CERTIFICATE OF DIVORCE AND SEND her AWAY.” 5 But Jesus said to them, “Because of your hardness of heart he wrote you this commandment. 6 “But from the beginning of creation, God MADE THEM MALE AND FEMALE. 7 “FOR THIS REASON A MAN SHALL LEAVE HIS FATHER AND MOTHER, 8 AND THE TWO SHALL BECOME ONE FLESH; so they are no longer two, but one flesh. 9 “What therefore God has joined together, let no man separate.”
10 In the house the disciples began questioning Him about this again. 11 And He said to them, “Whoever divorces his wife and marries another woman commits adultery against her; 12 and if she herself divorces her husband and marries another man, she is committing adultery.”

If she is a committed christian then she would not have to divorce him, because of his "abrupt " decision to withdraw from christianity. The couple would also need to seek some counselling at some stage - since the wife would be battling some hurt by the husband's rejection of what they had both shared , their sacred spiritual relationship. In terms of raising the children; since the family had been part taking in christian activities all along, it would be very selfish for the husband to suddenly put an end to the children's routine,friends,support structure and associations with the church. If children arent involved then the couple would need to take time to discuss and reach some agreement about how they plan to raise the children - I dont think the husband would successfully erase all the christian values from his household ; if his wife was a committed christian, because as the mother she would expose the children to christianity because that is who she is. Lastly the couple should maintain love and respect for each other.

Proverbs 3:5 Trust in the LORD with all thine heart; and lean not unto thine own understanding.
6 In all thy ways acknowledge him, and he shall direct thy paths.

What if that person was Christian but renounced the religion and sought to find him/her self in a more traditional African religion, took to wearing a Dashiki every now and then and talking about Yoroba or Kemetian philosophy...?

my hubs doesnt go church. only when there is a christening or weddinf etc
but he does believe. he feels he doesnt have to go. the last time he went he was like yeah i am gonna have to go sometimes.
not a major issue for me as long as he doesnt interfere with me or our sons church attendance