Among religious people, why is it that Muslims have the hardest time assimilating to western society?

It makes no sense to talk about assimilation in a multicultural country built on immigration and a blend of various cultures instead of the original one/natives.

I am an ex-muslim and I still refuse to agree and assimilate completely. I adopt what works for me and reject/discard what doesn't. Following blindly the majority doesn't strike me as an intelligent option. I like some traditional things because they appeal to my personal sense of right and wrong.

Muslims do not have a unified culture too. They are very different and diverse.