There are a few keys I think for overcoming addiction (former smoker, I vibe quite a lot with the running to quit smoking).

1. Feedback loops. Addictions tend to be positive feedback loops - 100% pleasure. EG: Sit on ass, smoke, feel great, continue to sit on ass, smoke more, continue to feel great. But, add running into the mix and that turns into: sit on ass, smoke, run, feel like shit. "feel like shit" was never part of that first feedback loop. At least "feel like shit" won't be until the lungs are damaged enough where they begin to have serious trouble repairing themselves. Even then, that feeling is masked by smoking (when a person smokes, pain suppressing hormones are released in and around the lungs). It could even become perverse, when a persons lungs start to hurt - they then want to go smoke. Identifying these positive feedback loops IMO can really help clarify what is driving a behavior.

2. Replacement. Are you sitting at a desk eating too many sweets? Try replacing with mixed nuts or another snackable. (I swapped alcohol for tea once and was pretty successful there)

3. Desensitization. Cook 100% of your own food for a month or two. At the end of that, you'll be eating a lot less salt and sugar. Going from that, to then eating a big mac or candy is going to be nothing short of an assault on the senses. The big mac will taste greasy, the candy over-poweringly sweet. It'll be easy to jump right back in the feedback loop and become re-addicted to this food, but the initial positive feeling will be significantly lessened.

4. Budgeting. Be careful with this one. This technique never worked for me, but for some it does. Allow certain things at truly specific times & places. This is how some people control coffee, for example: they get one cup a day, before 10am, period. Ask that person if they want a cup of coffee and they say "I already had my cup of coffee for the day." My willpower to do budgeting is close to zero, so I don't try this, but it works well for some people.

5. Inspection, why do you love it? Addictions are centered around love. I loved smoking. It's really a very nice thing to do, it's fun, it feels good, relaxing, something to fiddle & fidget with, reliable, a nice little break every now and then to enjoy the night air. Once a teenage peer said of drugs to me: "what's the worst, you won't like it and won't do it again?" Actually, the worst is you do like, and you wind up liking it a lot. We do these things all the time for a reason, not just because we are weak, but because we love these activities, that is why we're addicted. In this technique, simply seek to better understand - what is this activity doing for you? Why do you like it so much? What holes is it filling in your life? Personally, I thought there was something very empowering to absolutely state, "I love smoking", and I will always love it - that is why it is an addiction. Once you make that statement, I think it's easier to gain compassion and agency, and then it becomes easier to also start to think about why. Before then, the thoughts of being a smoker were generally things like "I'm just weak", or "this is a small vice, I'm trying to kick", or "I don't really like this, it's all meh, I'll quit soon." These latter things were all lies for me, confronting head-on that I was dealing with something powerful, and slightly more profound than "just a small little vice", was just really important. Without that, thinking about the situation really just got very negative, makes you feel like a failure as a person, thoughts that generally humans do not like to dwell on - so instead less thought is given to the vice and the habits just kinda continue. Instead stating, "I love this, now let me think about why?" puts it into a frame that the mind can dwell on.

I'm overdue to write a book on this. I hope my experiences/thoughts might be of some help and interest.