Whence Comes God's Pain in Labor (Isaiah 42)?

What is the source of God's labor pain in Isaiah 42:14? If the metaphor of labor fully applies to God's creative new restorative work in 2 Isaiah (as my post yesterday suggested), then this restorative work somehow involves groaning and suffering for God! How does this work?

Dr. Claassens in her paper interpreted God's pain in labor as God's work of entering into the trials and trauma of the people, who have been exiled to Babylonia as prisoners of war. In my response to her paper, I suggested another possibility that to me seems more in keeping with the overall theology and thinking of 2 Isaiah.

I suggested that the metaphor of God's labor pains in Isaiah relates to the pain to which a stance of vulnerability exposes one. When one lets go of control, puts aside the ego-self, drops one's guard on behalf of something greater than the self, then one is almost guaranteed to be in for great pain.

In 2 Isaiah God is seen to put aside God's right to justice, to put aside what's fair and deserved. Others should be doing their part, but God ends up having to pull everyone else's weight for them (cf. Isaiah 41:28; 59:16; 63:5). When you embrace other-centeredness, you often get "burned," you take the "fall," you open yourself up to misunderstanding and deep rejection precisely at a point where you have exposed your soft flesh. Is that the nature of the "pain" that God is feeling here in Isaiah 42?