If you want to know what exactly happened, keep reading, and thank you for your patience.
I do want to know exactly what happened.
Meanwhile, I was still a heavy investor on JD, the investment was in another account.
Your heavy investment was already divested before you won as nakowa, and was not reinvested until September. Here is the invest/divest log:
Sun Jul 7 00:54:12 2013 2706.84971987
Sun Jul 7 12:45:44 2013 -2706.9447692834683
Sun Jul 7 14:38:37 2013 7006.94381879
Mon Jul 8 05:33:41 2013 -7177.601611301108
Mon Jul 8 13:11:31 2013 7177.6016113
Tue Jul 9 05:23:59 2013 -7199.3705307143655
Tue Jul 9 07:16:13 2013 7199.33453365
Tue Jul 9 12:48:53 2013 -7249.307401082657
Tue Jul 9 23:00:41 2013 7246.80875771
Sat Jul 13 10:45:44 2013 -7289.945325680948
[nakowa and celeste played]
Thu Sep 5 17:55:50 2013 300.08272652
Thu Sep 5 18:24:34 2013 -300.09267765005444
Therefore, when I left café table for smoking and chatting with others, I still kept an eye on JDs stat from time to time. When I noticed from my iPhone screen that my investment rose up more than 10 BTC, I thought, wow, who lost that big!
The bankroll at the time was around 25k BTC. Your 7k investment would have grown by a lot more than 10 BTC when you lost the 1300 BTC if you were still invested.
When I went back to my table, looked at my screen, the browser opened, and the balance is 0.
You told me that you had deleted your google auth code so that you could not play any more, and that you could not log in:

That contradicts your statement above that you were already logged in.
I cleared my account balance on JD already, (another investing account was never logged in from this laptop), were you me, could you have any incentive to protect nothing?
Yes, of course. Even when I have no bitcoins on my laptop I do not leave it unattended and unlocked. It is trivial to install malware on it which will later steal your coins. Just because your balance is currently zero is no reason to think it is safe to leave your laptop unlocked!
You have google authentication enabled, others cannot login! YES, but I did left that GoogleAuth barcode image on the desktop screen, which you could call it my fault.
Who sets up two factor auth and leaves both factors on the same machine? That makes no sense either.
With all due respect, I have to claim that the main fault came from dooglus. The starting point was he forgot clearing the already withdrawn balance.
It is true; the mistake was mine. I was stressed and tired; you had been destroying the site's profits for hours, maybe days, and I made a mistake. It would have been decent of you to have returned the coins, but I understand it must have been hard to resist playing them. I find it very hard to believe the story you tell about what happened, sorry; it is just too implausible.
Edit: blurred avatar in chat screenshot as requested; text left unchanged
Edit2: blurred avatar even more
Edit3: blurred the name more; apparently you could still make it out