Welcome back, Etch!
My advice would be to make small changes gradually. If you're finding that you can't stick to a strict routine for more than a few days how will you stick to it for the rest of your life? When people 'fall off the wagon' it's usually because they've changed too much too soon in their lifestyle and every instinct in their body is telling them to go back to their old habits. And go back to their old habits is what they do.
One solution: pick one thing to change this week and stick to it. Don't worry about the rest of the stuff you need to change, that can be dealt with in weeks to come! Even if it's something as simple as 30 minutes of exercise, even just walking, per day. Or drinking more water. Or having salad with your dinner every night. The simpler the better because it will be easier to stick to and it will give you confidence to make more gradual changes.
There's a temptation to want results straight away, so many of us tend to fall into an all-or-nothing approach to weight loss plans. The thing is, the slower you lose the weight the more likely you are to keep it off. So accumulated small changes can be better at keeping the weight off in the long run rather than aiming for changing everything at once to lose the weight as quickly as possible.
It might be tempting to suddenly cut out all processed carbs, go to the gym for an hour a day and eliminate all treats because you see other people here who have done so successfully. There are two things to remember: first, successful weight-losers here have been losing weight for a long time. They probably started with only one or two changes and slowly they've built up to the incredibly healthy lifestyle you're reading about in their weight loss journals now. They didn't do it all at once! Second, you're you - they're them. Trying to copy their weight loss methods may not work for you because you're a completely different person! They may hate chocolate, love running, and enjoy getting up early for exercise. You may love chocolate, hate running, and prefer gentler exercise in the evening. The trick is to find out what works for you so that you can be a first rate YOU, not a second rate someone-else!
Good luck, Etch!