Oh the mad coupling of hope and force in which we merged and despaired. (37-38)
The love that the couple felt for each other was a crazy one. It seems that they tried to come together in their sorrow, but that the sadness was stronger than they.
what sorrow did you not express, in what sorrow are you not drowned! (44)
Hmm. Deflect much there, speaker? Does the speaker blame his lover for being too weak to overcome the sadness?