Several studies have shown that Mirtazapine greatly reduces cortisol in people (even healthy people). This is the hormone involved with stress -> guilt, anxiety, and eventually 'giving up'.
So if you're on an SSRI and still feel like 'not being around' anymore, this drug is the answer.
Here is the evidence:
http://www.ncbi.nlm....les/PMC2426820/
http://www.ncbi.nlm....pubmed/15677428
http://www.ncbi.nlm....pubmed/20381159
http://www.ncbi.nlm....pubmed/14561437
