Or maybe you are, heck maybe we all are. I dunno, really it's irrelevant. You can't change the past and honestly, you know this! Such an obvious cliche but the question remains; what are you going to do about it?
For a start you could simply acknowledge in yourself whether or not you are an inherently weak person or a strong person. If you are decidedly a weak person then the answer is simple, do nothing! Continue living exactly the way you are now and most conveniently nothing will change. The best part about that particular course of action is that it is easy; It actually requires very little, if any effort at all!
Regarding the latter, If you're certain that you are a strong person and that now would be a good time to start doing something about it, then might I suggest you begin simply by making a plan? Pick a priority and work on it one day at a time. When comfortable pick another one and so on until over time you have built yourself an arsenal of positive behavioural habits to fall back on in times of need!
I do realize the above stated advice comes off a little harsh but in reality we're all adults here, Either you are or you're not!
Lastly, just consider your own specific age and lifestyle habits. They were definitely not built overnight but through years and even decades of repetitive reinforcement and so how could you possibly expect anything to get better overnight?
Another classic cliche that now comes to mind, nothing worth having ever came easy! So go on now friend and put in the work, I mean don't you think it's about time you/we moved the hell on already?! #onedayatagrind