This is a one of the most obvious reasons why sex is important I think. Of course being intimate with one another is going to bring you two closer. The simple fact that you are seeing each other naked is enough to bring you closer. Sometimes being very much in love and being attracted to each other, doesn't mean the sexual chemistry is there. Once you two have found your groove in the bedroom, you should see that chemistry coming together.
Bhavin_Parghi