Re: Why Sufism didn’t flourish in west?
Monasteries do have a long and big history in europe.
With the rise in material wealth, it is difficult to keep sufi traditions alive though. Some even claim that hippie movement was sufi in nature. 
But essentially, I think Sufism has been influenced by Buddhists in India and hence stronger impact of monks and monstrosities and propagation of similar values.
https://lirias.kuleuven.be/bitstream/123456789/385351/1/Chapter4.pdf is an interesting read.