Then I remembered
how often I, too, had been indifferent to the grandeur of each day, too
preoccupied with petty and sometimes even mean concerns to respond to the
splendor.of it all.
你可能对最后的too...to do结构没有看懂。这是一个形容词短语作how often引导的宾语从句中的伴随状语,中心词为形容词preoccupied with petty and sometimes mean concerns。petty和mean都是形容词作concerns的定语,然后这个形容词被too... to do修饰,太...以致于无法做某事。