Well for one thing I have found that eating the wrong food can make me super lazy and depressed. So definitely take a look at that.
Also maybe if you found something to get addicted to (besides booz and drugs) like for example collecting bus ticket receipts or taking pictures of mailboxes (i'm trying to give you examples of weird things some people actually get addicted to). Anyone can get addicted to practically anything, the closer you look the more there is to see.