In reply to Phantom Disliker:
It helps to remember that blues is several things: a feeling, a genre, a black American cultural artefact and art form, a musical structure and form. I'm sure there are other ways of looking at it too. There are many variants, often sad but also dealing with many aspects of life as experienced by people who were downtrodden and poor. So some blues are a fight against the misery of life too - uplifting, life-affirming, danceable, funny, sexy... And even the sad themes of blues are often dealt with in a way that lightens the load, helps people come to terms with the miseries of life, both in the sound and in the sharing of woes.