Love/Hatred is part n parcel of our life, and we get engulfed & entangle ourselves with these, thro' out our life. We are happy when we get what we need and we become sad when things go in the opposite direction from what we desired for, which causes lot of distress to self n people close to us !! Siddhartha Gautama Buddha was experiencing the same in his life until he learnt many meditation techniques and finally settled in the technique he found - "Vipassana Meditation" which involves one step further from other meditation technique i.e to "Purify the Mind at the Root Level" by focusing the mind to "Observe the Subtlest Activity" & by remaining Equanimous he had cut down the misery caused due to Craving/Aversion and finally attained the "Enlightenment" at the age of 35 !!
History says he started to spread this technique thru' his 5 friends who together with Siddhartha practiced a diff meditation technique but left him until he mastered this technique and the word has spread to many people and even to one of the greatest Indian emperor - Ashoka The Great. Ashoka was calling himself "Cruel Ashoka" as he was conquering the world thru' his aggressive "Kill Any One & Capture" strategy, until he learnt the technique from Siddhartha and he helped spread this technique all over the world. Unfortunately the technique was lost in India after 5 centuries and as per the belief this technique would be maintaind in the pristine purity in "Suvarnabhoomi - Golden Land" and it will come back to India after 2500 yrs through a person.