My fiancee is an ISFJ and I am an ESFP. We love each other and enjoy each other's company. We can be serious together, but also really silly and playful. We can talk about anything and have a deep emotional and spiritual connection. But its still a relationship between two flawed people and therefore it's still hard and requires work on both parts. Sometimes it is hard and there are misunderstandings. We often have very different perspectives (which can be exciting yet frustrating sometimes). Sometimes the way we see things differently causes mis communication and misunderstandings. So we have definitely seen that communication is a place we need to grow. I think communication is one of the main keys to having a good relationship...regardless of what type each person is, if you can communicate and understand each other you will probably be happier. All that being said, communication is not the only thing that makes for a happy marriage. I have learned alot about myself and him and the more I learn about my ISFJ the more I see how selfish and prideful I can be, and yet how blessed I am to have him. The more that we learn about eachother the more we see that niether of us is perfect and niether of us are going to fulfill the other person or meet all of their needs. that is not what a partner is supposed to do, only God can do that. But we can try and love each other by helping each other along this journey of life. Neither of us are not perfect but we try our best to love one another with God's grace and the strength that he provides.