Lesson being learnt slowly but surely:
Guarding your heart does not mean doing whatever it takes to keep it from breaking. It does not mean making yourself less vulnerable, it does not mean pushing down emotions, and it does not mean building walls. Guarding your heart does not mean you will never feel pain or you will never be hurt.
But what guarding your heart means is placing the most precious part of yourself in God's hands. It means letting whatever needs to be felt to be felt. It means having hope in Him, it means trusting Him to walk you through darkness, and it means letting wounds be open so He can bandage them up. It means that there is no guarantees in what we go through, but there is a guarantee that He will be there.
His hands will never be too small to hold your heart. His hands will never be too small to keep it safe.