Obituary Sunday - A Suicide

U. S. Federal Census Mortality Schedule June 1, 1860

Bracken County, Kentucky

I don't have an obituary for my great great grandfather, haven't found any information at all beyond his wife and children, all I know is that he shot himself.  Why? 

 His name is John York, he is 28 years old and he is a farmer, and for some reason he committed suicide.  Why?  

Will I ever find out any more about what was going on in his life.  His wife was pregnant with their sixth child.  

Does anyone really ever know what causes a suicide.  I wish I knew what was going on in his life.