I was using cannabis nearly every day for a while - like you, because of mounting stress and anxiety. I've come to believe that most addictions are pursued because your brain basically wants to fall into a less anxious state, something it kind of knows will work, and you get in the habit of letting it do that. Part of seeing that for me was realising that you only get to be in charge of part of the goings-on of a working brain and body, and sometimes your influence on your own behaviour can be...subtle. ;)
Cannabis isn't very physically addicting by most measures, but it really does alter your view of the world in pretty significant ways - I never used very much relative to most people, but it makes certain kinds of interaction - like business and relationship stuff - difficult, and in my mind at least, less authentic (I think the same applies to prescription anxiolytics like SSRIs). The question for me came down to whether I trusted myself to get through a day - or eventually a week - without it. I believe that trust in others comes from trust in oneself, so this is a pretty important question to be able to answer about yourself.
I think that if you can manage your stress reactions at all (and a reaction to some difficult thing is all that stress ever really is), you can do it with or without cannabis. Weed is a nice vacation sometimes, but I got more control over my life when I decided that it was only good on weekends, after a certain time in the evening, or in certain social situations etc. Basically if this is going to be part of your life, let it be a rationally-chosen part. That means doing some introspection about what your use of cannabis is really about (luckily for you your drug of choice tends to lead to lengthy introspection anyway).
Finally, smoking or vaporising anything is inherently harmful and using cannabis in particular puts some small strain on your heart, so coming at it from that end purely as a harm-reduction approach means you need to use the smallest amount possible. That basically suggests it should be a treat, and that means you need to earn it with some weed-free time.
And if that sounds like I'm completely in control of it myself by now - I'm not. But I'm getting there. Just make sure you're aware of your use.
Just because you think your marijuana use doesn't get in the way of your life doesn't mean you're not addicted. Compare your marijuana use to a cigarette smoker who smokes every day to ease stress and anxiety. If the smoker's friends, family, and employer don't mind, he would probably say it doesn't get in the way of his life. Would you say that means he's not addicted? Probably not.
Part of addiction is doing something even though you know it has negative consequences. Smoking marijuana does have negative consequences--it's illegal, the smoke has been shown to contain 50–70 percent more carcinogenic hydrocarbons than tobacco smoke (although the link to cancer isn't proven), and it puts you at a greater risk for respiratory problems. If you continue to smoke every day despite knowing these things, I think that could be sign of addiction.
Click Here to search for a treatment center in your state that is right for you.