@ghazayel ... I might have ... crossing finger. Mine is stable.
It must have been one of 2 usually very reliable plugins: 1 is "WordPress SEO by Yoast" and the other is "Redirection". I was able to frame when this behaviour started - and looking in the plugin directories, I saw I updated only these ones after that date.
Now I rolled both back to previous versions (acutally I used a major release for redirection 1.3): stopped plugins, delete directories and loaded the olders via FTP.
Site is now stable from 24 hours. I cannot tell which of the two is the bad guy: being a production site I did not want to try with just one or the other. So I can only toss a coin :-D However - amazed as these 2 have always been EXTEREMELY reliable and I could never trace them to a sidebar or footer issue in widgets !!!
Not sure if this is tour case - but if you have any of them, try roll back to previous vesrions (around june).