Distressed Dreamer

I'm a 24 year old woman and am having difficulty understanding what's happening to me. I have always had vivid and intense dreams but last year as I slept with my boyfriend one night, I dreamed of my cousin Blake dying suddenly. It was so vivid and real. It was in a view like I was right beside him but couldn't wake him up. I couldn't tell what the cause was of all the distress but everything around us was shaking and there was so much blood, then silence. I awoke in a panic all sweaty and screaming. My boyfriend tried to calm me and remind me it was only a dream. The next day I went to a baseball game with Blake's parents present and felt a strangely strong urge to tell them about my dream. My boyfriend wasn't much of a believer and convinced me to stay quiet, that I would only look crazy. That weekend Blake and two of his co-workers crashed into a tree killing everyone in the vehicle. I know I should have said something that day, maybe I could have prevented it. I don't really know. But since then I feel shadowed in negativity. Like something ugly follows me around, making sleep a turmoil most nights leaving me physically exhausted and distant. Sometimes it's even hard to determine what is real and what was dream. This is causing me very much stress and making it literally impossible to connect with anyone on any level. My parents look at it as depression but I feel something else is present. I feel it and sometimes get a glimpse, and it is not Blake. I will appreciate any helpful insight to my situation because it only seems to be getting worse.