True, God is all sufficient and does not need our love.
But it was He who first loved us, and desires that we do the same to Him and one to another.
If we had nothing but these two commandments, "love God and love thy neighbor", could we interpret that without the experience of life and suffering?
'Need' and 'desire' amount to the same thing. Why does Almighty God require worship and adulation?
It is through suffering that the charter of love is born.
Suffering is not necessary for love.
In adversity, we either forgive or hate, good or evil, night or day, up or down, east or west.
There doesn't have to be adversity or any tribulations. And you keep mentioning good and evil, night and day, etc, as if it were logically impossible to have the one without the other.
The experience with credentials, is what will get us through it, be it for our good or for evil.
It has to be love from God first before I can learn to exercise it myself.
Yes, non believers in God can exercise love as well, but that is because it given us all in the form of a conscience.
Does a lion kill a baby deer because it has a conscience?
Yet, we feel for the baby deer, or have compassion for its inability to defend itself giving want for our help.
'Love' is a biological instinct, selfish and utterly essential for humans to procreate and continue their existence. And compassion, conscience and empathy are reflective emotions, and as with all emotions they are centred necessarily on the self.
Loving one another is best tested in an adverse conditions, giving degree to that love.
Then you're making suffering a condition for love, which completely negates its meaning. I'm sorry but what you describe is conditional and contradictory (if not an immoral concept!).