To believe there can be happiness without sadness is naive and self destructive.
God is the darkness and the light. We possess both aspects of this. It’s the attempt to overcome our dark side in ourselves and others that causes internal and external conflict.
“I form the light, and create darkness: I make peace, and create evil: I the Lord do all these things.” Isaiah 45:7
Now, I’m not religious, I am absent of any allegiance to dogmatic ideology. If I was to be put in a box it might be Agnosticism but that’s not entirely correct either. However I see the truth in the above.