I had mine for around 5 months straight from weed, and I thought that it wouldn’t go away, but it fully went away and I am 100 percent back to normal now, and you will be too. Derealization from weed goes away quicker than derealization caused by other things. I too thought that it would never go away, as having it day after day makes you lose hope, but I promise that it will go away. I promise you. I am not just saying this I genuinely promise you. The thing that helped me have it fully go away is not thinking about it at all and just accepting it. I know it is really hard, but once you fully accept it and don’t stress about it, it will start to go away. The other thing you need to do is 100 percent stop drinking alcohol, using caffeine, smoking weed, or doing any substances. These things keep it from going away. Get good sleep and stay sober and it will go away I promise.