It's addictive in the sense that it is a BP medication, it lowers it. Rebound heightened BP will occur will all its nasty side effects when removed too fast.
Yeah it's not addictive, it just has rebound affects when discontinued. Clonidine is notoriously bad for this and is one of the reasons it isn't used much by doctors for BP control. Once you start taking it for high BP it will be hard to take anything else because of the rebound affect when getting off of the Clonidine.
IMO Clonidine should be the last drug to use to relieve symptoms of withdrawal because it is hard to get off without having negative rebound affects. I started taking it when I got off pain meds and haven't been able to get off of it since because they can't control my BP without it. Another thing about Clonidine is that tapering doesn't seem to help with the problem. You just have to deal with it and in a case like me, where it gets so high there is no other choice but to use it to get the BP down.
Again this isn't considered being "addicted" because abuse, like taking more or more often then prescribed, is usually what is necessary to meet the normal definition of addiction. You do become dependent but I think there are a lot of drugs that make you dependent on them. When I quit taking Prilosec, my stomach hurts from hyper-acid production caused by the lack of the medicine. If you take anti-depressants and suddenly quit taking them, you will get extremely depressed. I take Benadryl to help me sleep and like other medications that help you sleep but don't necessarily give you a buzz, yet when I quit taking them I can't sleep for several days after I quit. Whether it is physical or psychological, I think all drugs have some kind of negative affects when you quit taking them after you have been for a while.
As you can see Clonidine's negative effects from discontinuation can be just as bad as whatever you are trying to get off so in a way it is similar to taking another opiate(like Suboxone) to get off of an opiate. Yeah it makes the withdrawal easier but does it really if getting off of that drug is just as bad?
If anything, only use Clonidine to relieve opiate WD as a last resort. Anything, even a benzo would be easier to get off of IMO but the doctors will not agree because they say it is another mind altering substance. Like I said a lot of drugs have withdrawal symptoms when discontinued and if it is easier to get off of one like a benzo compared to something like Clonidine, I think you would be better off with the benzo but I am sure many will disagree.
This, like most things related to a drugs effects on different people, is completely subjective and ones reaction and situation may be different so I am just giving an opinion of someone that has taken everything mentioned and what my experience has been. I also know a lot of others that have experienced the same thing. What is good for one person isn't always the best for everyone else.
Good luck and I hope you find something to smooth that out so you aren't suffering. I don't know how it works, but try some valerian root or other herbs that may help. Anything and everything before Clonidine. I think it's effects are probably more from the placebo effect then anything else because it never seemed to help more then something like valerian did and the negatives were far worse.