The idea that Buddhism is pessimistic religion that only sees life as misery and suffering is incorrect and only considers the first 2 of the 4 noble truths.
The 3rd and 4th noble truths describe that a cure for this suffering/stress definitely exists and describe the method to follow to reduce/remove this suffering and stress and to increase ones happiness- and a path that ultimately is said to result in nibbāna - the deathless state of infinite possibility & bliss (not the annihilation of self) see: https://www.accesstoinsight.org/lib/authors/thanissaro/nibba...
> Buddhism saw life as bitter, dominated by pain and suffering due to attaching possessions and material desires
The "due to" seems to be saying the same thing as you: there is a solution/way.