An example of 10 years union of duals which broke:
Igor Petrenko (ENTJ) and Yekaterina Klimova (ISFJ)

Among Igor's remarks about problems he blames only himself. That he used alcohol and often felt tired to pay enough attention to her. That there were long breaks when he for weeks and monthes was not at home, sometimes they could to not talk for weeks.
Good IR need close relations to work as should, - when people get a distance psychically and physically - types factor reduces.
Duality helps with a friendship. People may use this by sharing one life together - when they do many things together, when exchange by personal thoughts and feelings, when are physically close.