Why Do We Make Friends?

Over time, I have been obsessed  with the hunger to find a sound answer as to why we have friends or try to make friends and I am almost sure that most of us do not even know yet we boast of having a lot of friends.

When I was much younger even up till this stage in my life, there were some shit that I did, my parents never knew and still do not know but a few of my friends have the details and a whole lot of other examples through experiences. I believe you have had similar thoughts run through your head too;....Why do we have/make friends? Simple: TO BE THERE FOR EACH OTHER WHEN WE NEED IT THE MOST.