I'm torn on whether or not Benwick really was suicidal. On the one hand, Benwick has shown himself to be of the extremely melancholy sort, and possibly prone to depression. He enjoys the Romantic poets, which are full of volatile emotions and tragic love stories. On the other hand, his behavior sometimes reminds me a little of Marianne, such as this part: "...he repeated with such tremulous feeling the various lines which imaged a broken heart, or a mind destroyed by wretchedness, and looked so entirely as if he meant to be understood..." and "...with a shake of the head, and sighs which declared his little faith in the efficacy of any books on grief like his..." (Ch. 11). Perhaps his melancholy behavior has become almost a habit to him at this point.