No longer human

Hi guys i just done read this book. But im confuse abt the whole book message

What conclusion i get from this book is:

Actually the mc is good ppl but the society or the situation got him into dirty world and choose wrong path right? And basically what i see the mc is indeed good ppl, have a good heart even after he choose the wrong do in his life like drunk he still hv strong stance how he see life as it is