It is very possible for the dead to try and communicate with the living. Sometimes they don't want to leave the ones they love behind or they just want to remain close. If your friend was to ever approach you try and talk to him.
An additional suggestion: While agreeing that it may be the spirit of the dead is reaching out to your living friend, it could also be that your living friend has been deeply troubled by this suicide, and could even be feeling guilty or afraid. As a good friend, you can encourage your living friend to talk about the experience, listening carefully and offering reassurance that the world is full of forgiveness, grace and new beginnings.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.