Coping with relationship stress varies according to what the issues are. In my practice it seems to me often that people are stressed in their relationship because their are communication problems in their relationship. If we could stay on top of this by using good communication skills then it is possible to have a better relationship and feel better as well. I often recommend the book The Feeling Good Handbook by Dr. David Burns. It not only offers great material on learning Cognitive Behavioral therapy (CBT) but also has what I believe are excellent chapters on building communication skills.