Timeline, sequence and video dissapeared

During the past 2 months i've edited a video which consist of 12 different projects. I was finished, exported evertything and pasted all in 1 sequences together (I did it this way since my mac crashed 24/7 if i tried doing this in 1 sequence). I discovered that there were some sound bugs which totally ruined the project and some video bugs where the video file was corrupted (green and pink boxes covers the video clip. I had to fix this, but then something terrifying happened. All my timelines and sequences have dissapeared and I cant find them. If i open the project only the unedited files are there, which sets me back several weeks. 

Ive tried to reset to saved layout, import the old sequence etc etc, but nothing works. please help!