All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
The marriage contract is valid if the conditions of a correct marriage are met, the most important of which are the consent of the guardian and the presence of two witnesses. If the marriage took place with these conditions, then this woman became your wife. As regards conducting the marriage contract in a church, this is not permissible, as this will certainly include some of the rituals of the non-Muslims, and it is forbidden for a Muslim to attend them. For more benefit, please refer to Fatwa 87484.
Moreover, a Muslim is not permitted to permanently reside in a non-Muslim country, unless in case of necessity or dire need, as we clarified in Fataawa 86405 and 81464. The fact that you are residing in that country does not make it permissible for you to commit this forbidden matter, which is conducting a marriage contract in a church.
Nonetheless, if there is a necessity or a dire need in residing in that country, then you should find a means to reside in that country without resorting to conducting the marriage in a church, which is a disadvantage and harm that is not permissible for a person to undertake unless it is an obligation on him to do so in order to remove a harm that is religiously considerable.
Allaah Knows best.