“ I went out full, and YHWH has brought me home again empty. Why do you call me Naomi, seeing that YHWH has testified against me, and Shaddai (the Almighty) has afflicted me?”
And now God had made Himself know to Naomi as YHWH. While in the foreign land He had acted towards her as Shaddai, but He was now acting towards her as YHWH. She had gone out full (having a husband and two sons) into a foreign land, and there God had afflicted her as Shaddai and by that means, as the covenant God YHWH, had testified against her as one who had departed from the sphere of the covenant, but it was as YHWH that He had now brought her home again empty (having no husband and no sons) because she had previously removed herself from within the sphere of the covenant.
Note how Naomi equates Shaddai with YHWH in the Hebrew parallelism. It was as Shaddai that He had afflicted her in a foreign land, but it was as YHWH that he had testified against her by this action because with her husband she had removed herself from within the sphere of the covenant. And it was as YHWH, the covenant God, that He had brought her home within the sphere of the covenant, into the land where He had ‘visited His people by giving them bread' (Ruth 1:6). By His affliction in the foreign land she had ‘known Him' as Shaddai; by His bringing of her home within the sphere of the covenant she now ‘knew Him' as YHWH; and she recognised that that it was because of what they had done by leaving the sphere of the covenant that she and her family had suffered.