In my twenties I had a beverage diet that consisted strictly of soda, energy drinks, cocktails (on the weekends) and an occasional sports drink if I was dehydrated from too much partying.
At some point in my late twenties and early thirties, I started realizing this addiction needed to change. I began by just cutting back on how much soda I was drinking, choosing to alternate with water and other alternative drinks. I started "crowding out" soda by bringing healthier beverage options in rather than just going cold turkey, failing and deciding I couldn't do it.
In my experience, I found that having a goal is key. In my case, it was choosing a healthier lifestyle. Once you have that goal, keep that at the forefront, but also remember you are human and trying to change a habit/addiction you have had for X number of years. Another key to quitting soda is having desirable alternatives. Find what you like, allow yourself to invest in your health even so you can get to your end goal of having a minimal amount of soda each day.
I found mineral water to be a great alternative, I loved the carbonation of soda. I add in lemon or lime juice for flavoring, lemons and limes also have great cleansing qualities. I also started drinking a lot of tea. It took me a little searching and some great tea shops to find the teas I love, but now I drink tons of tea, which have so many added health benefits. Fruit infused water can be another great alternative for some.
Give yourself some time to experiment and find some alternative drinks that excite you and that you can enjoy sipping on. Keep reminding yourself of your goal- whether it's about your health, your teeth, energy levels, setting an example for your children, whatever it is keep your focus on that. If you're having a hard time remember to be kind to yourself and treat yourself with compassion, the negative self-talk in my experience only sends me into a deeper spiral and I end up in a constant mind battle with myself. Being compassionate with yourself doesn't mean you quit or make excuses, it's recognizing you are human and you are doing the best you can in this moment and that you are going to keep trying the best you can. You will reach your goal. If you are moving forward even if it's just one step a day, you are succeeding!