Funny thing you mentioned it. While I personally think nobody should read his works, Houellebecq is the writer to peruse after contracting a terminal case of spiritual malaise. One thing I want to add is that Houellebecq's body of work is an assortment of potential solutions to this modern day problem which has become more pronounced in the US lately.
The Extension of the Domain of the Struggle (Whatever) is his first novel. The motif is that similar to economic inequality, due to sexual liberation, the sociosexual arena has become more winner-take-all, hence the extension in the title. The plot chronicles the disillusionment of a sexless programmer in denial after going on a road trip with a similarly dysfunctional co-worker who ended up commiting suicide. The story ends the protagonist going postal but offers no practical solution.
His next book The Elementary Particles follows two half-brothers who were dysfunctional in opposite ways. One was a complete sex addict who failed to individuate and the other became a monk like molecular biologist responsible for making sexual reproduction obsolete.
His next novel Platform is an in-depth analysis of the discontentment of sex tourism from the perspective of his alter ego, which is clearly formed by his own lived experience in Indonesia. I think it's his least coherent work FWIW.
The Possibility of an Island arguably follows the timeline of Atomised and describes the nature of love through the narrative of three clones of the same person from the hedonistic present, totalitarian future and hunter-gatherer post-apocalytic future.
Submission is about the return to traditionalism after a Muslim party won the election in France. The effect is complex but nominal as we all know there is no going back.
I am waiting for the English translation of Serotonin which should be released before end of next year.