For a book on the Kurdish struggle I suggest Blood and Belief it talks about the history and development of the PKK, which is possibly the most popular Kurdish nationalist group right now and have a sister organization that runs Rojava. It also briefly dives into the issues between the PKK and the KRG in Iraq. It's really interesting.

Depends on which Kurdish struggle you're referring to

A book I've been reading that was recommended here for the Sunni Shiite rivalry was "After the Prophet." Check it out, really good read.

I thought Vali Nasr's 'The Shia Revival' was quite good regarding Sunni-Shia relations.