A my little pony and Left 4 Dead crossover.

After Spike loses a very valuable book Twilight desperately seeks a way to purchase a new copy. Hearing that the community center needs a temporary stand in for it's therapist Twilight signs up without a second glance at the contract. You see the therapy group she has decided to fill in have issues of another type altogether. Does Twilight have what it takes to cure a biker who believes himself to be invincible, A college student who's clumsiness has lead to the most unwelcome of stalkers, an IT tech who's addiction endangers others even more than himself? Or a crotchety old man who may or may not have really been in the war. One thing is for sure after 5 minutes with them Twilight understands why the last therapist took a vacation with no return date.

"I've only known the company of myself for years since my grandfather's passing. But one night a message in a chat room would change everything. Soon after that I met my new best friends and the trouble that follows them around. My body and soul belongs to mother now and as long as I live so will she. And try as I might I can't bring about my own end to put a stop to her. Someone save me from myself."
-Daylight Storm

An ex human becomes the living vessel for a recently defeated Nightmare moon. Through her power his broken body adjusted to survive in the magical land of Equestria he does her bidding along with his fellow slave another Ex human who takes the pony name of Lyra Heartstrings. The short time spent with his close friends is a distant memory and he is tortured by the fact that he is so close to them but so far away as he helps Nightmare moon plot to reclaim Luna as her true vessel. Breaking free will not be easy as the queen of darkness knows his every thought. Will he and Lyra escape? Or will they help bring about the true return of Nightmare moon and her cohorts?

"Tragedy begets the best comedy"
-Nightmare moon