Purpose in life is so important that you live longer if you have one. Purpose starts with identity. First your identity at home: mother father etc, then your identity in the local community: your occupation , then your overall community identity which determines your shared values and goals. Identity is the starting point of purpose and in most cases purpose is to fulfill your identity as well as you can. Your personal identity may change throughout life ie father to grandfather. Thus purpose in life is fulfilling ones rolls in life as well as we can for the good of our family and community. Career is the big lie as 98% of work is a job defined as something you would not do unless you were paid. There are some especially on the Asperger's and psychopath end of the spectrum who seek identity my marking the pages of history. Therefore know thyself. Know the identity that suits you. Ie either work to live or if you belong to the latter live to work ideally without family as work has replaced family.