Why is there strife and violence in our plane? Because we,as humans, create it.
David creates a false dichotomy here. Either God is a loving God or there is strife and violence. Jesus said "rend unto Caesar what is Caesar's, but render unto God what is God's". He also said "I am the Alpha and Omega".
Note that Jesus did NOT say "I am the Alpha, the Beta, the Gamma, the Delta..." et cetera. Our universe was indeed created by God, and out of love for us, He granted unto us free will. But the current plane of our existence isn't the end game. Jesus mentions many times that our ultimate reward is with God, not on this Earth. The "rend unto Caesar" comment is essentially saying "hey, this is YOUR Earth. God created it for you, and you have the will to do with it whatever you choose. God is not concerned with whatever rules or acts that you humans decide to promulgate on this plane. But remember that in the end ("the Omega"), all of this will be gone and you will be summoned into God's presence. Jesus said on more than one occasion that there are only two Commandments necessary to follow in order to be summoned to the uiltimate peace: Belief that Jesus is indeed the Son of God, and the Golden Rule. Other than that, humans are on their own. Jesus gives us a number of pointers to make our existence here less violent and less stressful - don't throw stones, turn the other cheek, don't be obsessed with things or money, forgive others...and when we don't do that, we bring strife and violence upon ourselves. That doesn't mean that He doesn't love us. Just as a parent must sometimes watch an adult progeny make bad decisions, so God watches us. He gave us free will, much as a parent lets the progeny leave the home at some point of maturity. The parents will alwqays love their children, always forgive them, but cannot live their lives for them. The relationship between God and us is the same. We describe that as being "God's children", which is a bit of a simplification, but is made to be understood by the masses.