For a seeker to appreciate and comprehend certain character traits are of utmost importance.
Shall feel blessed if some blessed one could explain the philosophy of love and hatred in spiritual parlance keeping in mind the Advait Darshan.
The following are excerpts from the teachings of Sri Ramana Maharshi.
An educated visitor asked Bhagavan about dvaita and advaita.
M.: Identification with the body is dvaita. Non-identification is advaita.
D.: I understand theoretically. But they are still there.
M.: Yes. It is like a cinema-show. There is the light on the screen and the shadows flitting across impress the audience as the enactment of some piece. Similarly also will it be, if in the same play an audience also is shown. The seer, the seen, will then only be the screen.
Apply it to yourself. You are the screen, the Self has created the ego, the ego has its accretions of thoughts which are displayed as the world, the trees, plants, etc., of which you are asking.
In reality, all these are nothing but the Self.
If you see the Self, the same will be found to be all, everywhere and always. Nothing but the Self exists.
This is about advaita in brief.
So everything boils downs to the false identification of one's SELF to one's body. Then rises the EGO or "I".
Our emotions like LOVE or HATRED or JEALOUSY or HAPPINESS or SEXUAL IMPULSE and so on, are arising because we are identifying ourselves with our bodies.
I think the Bhagavad Gita explains this very succinctly:
ध्यायतो विषयान्पुंसः सङ्गस्तेषूपजायते । सङ्गात्सञ्जायते कामः कामात्क्रोधोऽभिजायते ॥
When a person keeps thinking about an entity (both animate (person) and inanimate), he gets attached to it. From attachment comes desire (to possess the entity), from desire comes anger/hatred (due to not being able to possess the entity).