The way I see it, we are made in image of God (Genesis 1), and conferred with choice. This in my understanding means God also has choice, and deliberately has chosen to be love.
Since whatever He (God) chooses to be automatically is, ‘God choosing to be Love’ is tantamount to ‘God is Love’.
Choice, however, is explicitly connoted in Jeremiah 9:23–24, which states,
Thus said Jehovah: Let not the wise boast himself in his wisdom, nor let the mighty boast himself in his might, Let not the rich boast himself in his riches, but let him who glories glory in this, that he understands and knows me, that I am the Lord who practice steadfast love, justice, and righteousness in the earth; for in these things I delight, says the Lord.
Could be important or not, but is logical extrapolation of the fact that we are created in image of God, and God’s declaration that He delights in love. This of course implies He chooses to spend His time in acts of steadfast love.
With respect to loving of the self, I am sure you have heard of people who mutilate themselves.
Appropriate godly love of the self never can be taken for granted.