Make a list of all those things you want to change. Pick just one to focus on THIS week. Make sure though, that it's something small that you can measure in some way.
For example, you can't say "I'm going to eat better", because that's too big and too vague. Instead, pick something even smaller and definitive like "instead of eating ice cream after dinner every day this week, I'm only going to eat ice cream 4 days this week". That's probably small enough that your brain won't make a huge fuss over it, and is also easily measurable. If you successfully make that change and can keep doing it for two or preferably three weeks, then you can more on. For example, maybe after three weeks, you decide to move to only eating ice cream once a week. Again, you need to be able to successfully do that before moving on again. If you fail, no worries, just try again. If you keep struggling, you may have picked something too big and you need to scale it back.
I would also recommend alternating diet and exercise goals. Thus if you successfully made a diet change that you're able to stick with, next time maybe it's "I'm going to walk after dinner 3 days this week". By alternating in this way, you'll find the diet changes are easier to adjust to and at the same time, you'll be improving your health. Just make sure to go slow with these as well. I often see people in the gym (especially this time of year), that tried to go from basically doing nothing, to working out 5+ days a week. Sadly, the failure rate for such people is well north of 90%.
Here's the thing. This will take a LONG time, but if you try to go faster because you're feeling impatient, the likelihood is that you won't be able to maintain the loss, you'll fall off the diet, and before you even realize it, you'll be right back where you were before.
I also want to be clear, I do still recommend seeking out counseling for a possible eating disorder, as well as help from an RD. Dieting is HARD. if it was easy, we wouldn't have an obesity epidemic. The smart play here is to stack the cards in your favor by getting help from experts.