It is in fact easy to understand Islam. You need to study the Eitz Chaim of Isaac Luria and you will see that the Dark Side has many aspects to it. It has an open aspect  That is what is called the Satan or male aspect of the Dark Side. That is Islam. That is the male aspect of the Sitra Achra. And there is a softer aspect the Female Dark Side, i.e. the side that disguises itself as a mitzvah.

We find in the books of Jewish Ethics [Musar] that there is a problem in joining evil people So it is important to be able to discern if some person or group is perhaps the Dark Side [Sitra Achra] in disguise. Books of Musar commonly bring this from the verse where the prophet Isiah told king Hezekiah "" when you joined together with Achaz, God made a breach in your works."
בהתחברך עם אחזיהוא פרץ ה' את מעשיך