I'm a Christian as well, and I deeply struggled with the thought of abandoning my commitment to my XAH.
A few things really helped me--
My pastor told me that God didn't ask for self-sacrifice. Marriage is a binding commitment by two people, and my H had essentially left the commitment by placing the marriage below his addiction. He was already gone and I was holding onto a ghost of a promise. And I said--What about sickness and health? Wasn't this the sickness, or the horrible times we're supposed to be patient and weather? Well, yes, in the beginning. There comes a time where it's no longer just "sickness" or "bad times", but a repetitive destructive pattern of abusing the marriage. I was only 50%.
He pointed me to sections of the bible that talked about God hating divorce, etc. But he said we take that literally--when the true meaning is that God cannot stand the pain we go through when someone breaks that bond...and that the bond is already broken when one person chooses AGAINST loving and honoring their spouse. The divorce had already happened, and the pain was already there. Me holding it together out of respect for MY HALF of the promise was not marriage in God's eyes. It was already over when he continually walked away from it.
I read a lot about it, prayed a lot, and hung on way too long in my own situation. For a long time I prayed for guidance on how to be patient, loving, forgiving, helpful--whatever I could do to preserve my family.
When I hit the end of my rope I finally gave it to God (which I never really understood before as a control freak, but I was exhausted). I simply prayed, "please show me what you want me to do".
For me, that path opened almost immediately and was NOT what I expected. It included a divorce, a job 1,000 miles away back home where my kids could be surrounded by family and friends (that paid for my move), no fight from X on me leaving the state, and a house I could afford in the neighborhood I had previously called home (that I bought virtually sight unseen). Within three months, I went from utter lonely despair to my own home surrounded by friends...terrifying to DO, but when I opened my heart, I truly believe it was laid out for me to see and pursue in a leap of faith.
That was 3.5 years ago. I have no regrets and feel blessed every day. By the time I decided to leave, I knew I it was right.
Hugs and prayers that you'll find the right path for you. Whatever it is...I believe that with an open heart you will find it.