The patterns of addiction in most stimulants -- most dramatically in crack cocaine (and often injected cocaine) -- is different from the pattern in opioid and benzodiazepine addiction.
Rather than having to either use one-to-several times per day or experience protracted physical withdrawal after developing dependence (opis, benzos, barbs, eventually alcohol), stimulant "addiction" -- if you wanna call it that -- is characterized by periods of relative abstinence (days, weeks, even months or years), interrupted by intense periods of bingeing. Stim users typically experience much less noticeable bodily withdrawal symptoms, but intense depression and malaise after binges or when they abstain longer than usual. So you might smoke crack only once every two weeks, but go on $500 benders where you take another hit every few minutes for days on end without sleeping. Some people don't really consider that "addiction," but I would if the person wishes they could stop bingeing but then feels they can't resist doing it on a regular basis.
Heroin or benzos, you take some every morning when you get up, and keep a relatively steady intake over time (think methadone maintenance, an extreme example).
My own perspective is that addiction is having the belief you should quit a drug, but then feeling unable to stop despite that belief. Feeling "out of control" over use (for crack, a few hours at a time; for heroin, 24/7).
I would describe myself as having been addicted for long periods to all the drugs mentioned above -- among others.
