I do not think under any condition does God want you to leave your children...They will see this as abandonment even though they may be with their father....You are being manipulated to think that this is a good idea so you can get out of the snare that satan has set for you by living with a man...Your children are to be your first and foremost consideration....God is able to seperate you from this man but you must also be willing to do what God wants you to do....I would encourage you to start attending a church where you are at and take your children with you when you go to church...Reach out to God and His Bride for help and become strong in the Lord so you can make right decisions...Most churches do not condemn persons in your situation but love them just as they are as Christ loves you and the man you are with....Blessings