Most of us will have to live with things that we don't understand. It's frustrating and can be haunting.
One thought though to which we can cling, is that God knows us better than any other. He even understands and cares for those whom we struggle to love and understand.
He knows us in detail and in all of our complexities. He comprehends all things when we cannot.
When feeling misunderstood and/or alone, we do still have choices.
The most ideal choice is to lean into God and to accept that His love and grace are sufficient. As we draw on this love, a perfect love, we become a well of His love that can then flow into the lives of others.
We can feel alone and forsaken but this is not the one and only God. He does not leave nor does He forsake us. (Deuteronomy 31:8)