From my point of view there are two types of relationships:
1. Complementary relationship- where two people with different personalities fit each other like yin and yang, which allows them to cover for each others faults and mishaps, also to allow each other to discover more about their other half.
and
2. Similar relationship- where two people of similar personality and traits come together, this allows them to find common ground and relate to each other more easily.
What do you think? and which type of relationship would you prefer?