stopping won't make you not be able to go to sleep. It'll just make it harder, or you'll just have to go to bed later than you usually would. You probably will only get depressed if you think you will. When i quit for a month it's not as bad as you think it might, it almost made me wanna stay sober for good. But, just excersize a lot all the time, that'll release the thc outta your fat cells quicker, and you'll just feel good all the time if you do it right. it'll be worth it in the end.