Imaginary Friends by Stephen Chborsky

Christopher has had too much trauma in his young life - his dad is dead and mom's latest boyfriend is an abusive creep which is how he and his mom ended up in this little out of the way town. Instead of life calming down, Christopher gets more agitated and becomes driven to sneak out at night building his treehouse and doing anything else the "nice man" tells him to do. Mom doesn't really know how to help Christopher and is becoming more and more alarmed at the whole conversations her son is having with a plastic bag (his imaginary friend). This is pure horror - good people dealing with stuff way over their heads and involving children. Classic battle of good and evil and a must for fans of Stephen King, Joe Hill, and other horror writers. If I could have read this 700 plus page novel with my fingers covering my eyes I would have.