So, I have +60h of Witcher 3 and always runned just fine. A little stutter now and then but solid fps rate and fluid play.

I stop playing one month or two and recently come back to game again.
I did all the updates (I play through GOG Galaxy) , load the game and now, it seems that my laptop is a toaster. Slow responses, low fps, pretty much unplayable.

I lowered graphics but nothing changed. I optimizes through Nvidia GeForce Experience but nothing changed. I loaded a older save to see if the recent save was corrupted or something but nothing changed. I reinstalled the game, nothing. I rolled back to older updates, nothing
.
I don't understand. I played 60 hours so well and now it's unplayable. I really want to finish this amazing game but I don't know what to do. I really need some help.

I can't help you with your question. However, you posted this in the Witcher forum and I think you might get more help if you post this in the Witcher 3 forum. ;-)

Ooops, sorry about that. What should i do? Delete post and do another in withcer 3 forum?

No problem. Since you can't delete old posts, the new one in the Witcher 3 forum should be enough. :-)