You said you can't seem to find an effective way to cope. What have you tried?
Have you tried creatively dealing with them? Writing, drawing, photography, poetry, etc.
Exercising will make you feel better afterwords, but it's never really helped me cope through something. And I've never tried meditation or yoga, but everyone says that's good for stress and relaxing.
If the recurring thoughts are inevitable, you could meet it head on. Take some time, put in some calming music - or not, whichever - and let your mind wander through your thoughts. You can write your thought process down on some paper, or type it up, or draw little doodles. It might be a little immature of me to say this, but I like coloring. As in coloring books, etc. I used to think that the pictures in coloring books were set in stone and could never move until I colored them in. I'd color in an arm here and the character would be able to move it, then I'd color the head in, and they'd be able to blink and breathe and tell me how thankful they were and all the things they were going to do now that they could move. I had a pretty overactive imagination when I was a little kid. lol
And, of course, there's always talking to a trusted friend or loved one, speaking with a counselor, keeping a journal, posting on here or another forum that will give you good feedback.
Don't know if any of that helped. Good luck