As a person who greatly loves observing other people, one of my motives for doing so is seeing what sort of people are around me. To what extent are there similarities of approaches to life that may provide a bridge to mutual understanding, and to what extent do people have complementary traits to me, where our getting to know each other may help to provide a balance by allowing both of us to focus on strengths, knowing that there is some help in areas of relative or absolute weakness. I am fairly transparent about my desire to focus on my strengths to the greatest extent possible while also having a large enough network of people in my life who can help me in areas where I have rather serious shortcomings or vulnerabilities . Likewise, I am generally very open to using my strengths to help out others in their own plans and ambitions; I tend to believe very strongly in the importance of service to others and being willing to give to others that which I desire for myself.
Many times, our similarities with other people depend on the way that we frame the comparison. There are times where similarities, after all, tend to drive people apart. For example, if two people are both intractably stubborn and strong-willed, and happen to disagree, they are probably not going to be able to get along for all their similarities. Likewise, two people that both love to be the center of attention will probably not get along unless they find a way to perform together and draw attention to both of them somehow. That said, there are plenty of commonalities that bring people together. People who share a love of the same activities, like performing or reading, or various fandoms, often find a great deal of community in those shared interests and the shared activities that result from those similarities. That said, such interests can be greatly complementary. I am a writer, for example, but would find complementary relationships with those in shared interests with other writers for mutual encouragement of our writing, with book agents and editors and marketing people and others who could help my works find their intended audiences. Likewise, as a singer I am a tenor (with some exceptions ), which means that I would find a pianist as well as sopranos, altos, and basses to be complementary people for various singing performances, and so I tend to find myself around such people often, so that we can all create something beautiful together that is improved by the blend and the harmony. It is for this reason that we tend to treasure good relationships, because they allow us to be better together than we would be alone.
Sometimes, though, the framing of what similarities are meant draws strange parallels between two people. There are people I would not necessarily see myself as being similar to, for what might be considered somewhat superficial reasons, but when the qualities and comparisons were framed correctly, the result is generally recognition of rather intense similarities. Sometimes these similarities can lead to a great deal of emotional understanding and some rather serious areas of conversation that tend to come naturally. A greatly underestimated area of life is the way that we frame conversations and discussions, setting the appropriate borders of the conversation, setting the stage with mutual respect and concern, and seeking whenever possible to alleviate the perhaps inevitable tensions and anxieties that result from serious situations (at least for me). How to put things correctly, how to set the stage properly, how to set the proper boundaries, those are constant concerns, and areas where growing in skill would be immensely useful to myself and many others I see who struggle with precisely the same difficulties.
 See, for example: