In love with a murderer

Hi my name is Mackenzie, Mack for short. My bestfriends name is Alex, she was the perfect bestfriend. She was goofy, always positive, very smart, and beautiful. Notice how I said, was, what I mean by that is she's dead. She got murdered a few months back, by who? Nobody knows but we're working on it. While all this chaos is happening there's a new boy in my school and he's a cool kid, and I kinda like him. But, there's one problem, he's a suspect in my bestfriends murder. It's definitely not him...or am I wrong.