Sometimes maybe it seems I have too much confidence in resources to save marriages. I realize the real confidence is that when at least one party is willing to try, Jesus can save seemingly impossible marriages. Many of the resources I share directly point people to Jesus and His principles.
Even some resources that are not overtly Christian often share a lot of Christian principles. Dr. Phil, from my memory of reading his work, quietly talks about his faith and where he goes to church. Many secular resources now are talking about the benefits of such Christian concepts as forgiveness.
Sometimes in my own crisis situation I backed off on resources specifically geared towards saving marriages, and moved more toward ones that grew my relationship with Jesus, such as Believing God by Beth Moore. One of the things that I was believing God for was the healing of my marriage, but in that study I also learned a whole lot about Jesus and His Word that has application for all of life.
It is amazing when you think about it that as important as marriage is to God and how thick the Bible is, how short the Scriptures are that specifically talk about marriage and divorce. I think this is because He shares all over the scriptures about how to have good relationships. So, if we apply those relationship principles to marriage, we will have a good marriage.