Two are better than one, because they have a good return for their labor. If either of them falls down, one can help the other up. But pity anyone who falls and has no one to help them up. Also, if two lie down together, they will keep warm. But how can one keep warm alone? Though one may be overpowered, two can defend themselves.
A cord of three strands is not quickly broken.Is your marriage, at its heart, focused on God? If it is focused on anything else, there could be problems. The two of you need to constantly try and discern what God's will is for you - as a couple. To do this:
Pray. Pray for each other, and with each other. As a couple voice your concerns and your hopes for your marriage to God. When done together, it is a window into each other's soul. Make it a point to thank God for the gifts he's given to you both each time you pray.
Study. Be continually in God's word. The Bible has so much to say about God's plans for strong healthy marriages. Scripture is our ammunition against all the things that erode at marital happiness over time.
Seek. Make sure you are constantly seeking God's will for yourself as an individual, keeping in mind that you are "one flesh" with your spouse as well. Balance is sometimes difficult - but it is critical. Visualize your marriage as a triangle, with God at the top and you and your spouse at the bottom two points. If you are both moving closer to God, you are moving closer to each other as well. The opposite also holds true.