One needs to be on a different level of consciousness to appreciate the primordial fact that we are interrelated with our physical surroundings, the types of friends and relatives that we interact with. We also interrelated on these things on a psychological level. Positive interactions with the elements of these surroundings have a positive impact on us and the negative will a negative impact. This, in turn, affects our metabolism...When we are not in a good mood, we cannot enjoy good food, good company and thing like these.
At a deeper level, we are related to our past-in the present life and also to our past in the past life form. We carry imprints past life learnings and conditioning which affects the way we are prepared to see things in this life.
So Interrelatedness is the fact of life.. the more you accept this the more insights you can have on different aspects of life.