Help! How to flick the switch?

I think the key is not to approach it as all-or-nothing. You didn't put on the weight overnight and it's not coming off overnight. Losing 2 pounds a week sounds fabulous but it involves a pretty drastic calorie cut for most of us. Maybe try aiming for 0.5-1 pound per week.

Start by making small changes that are more likely to stick. For example, I started by cutting back from 2 tsp of sugar in my coffee to just one. From there I made other small changes. One small glass of wine with dinner every few days instead of a big one every day. Some people can cut out all carbs or whatever but I like food so I just eat what I want in smaller portions.

The other thing that really helped was figuring out my TDEE. Do a search on here for the topic and then work out your numbers. It's often suggested to eat at TDEE minus 10 or 20 percent. Once you know how much you should be eating for your height/weight/activity level then it gets easier to make good choices.

Finally, consider getting a Fitbit Zip or similar as a starting point. It tracks steps, distance, and calories burned (you do need to enter basic stats like step length to set it properly). I find that looking at my Zip each day I can see if I'm being a lazy slug or if I'm on track. This motivates me to move more or eat less, etc. Good luck!

I can totally relate! I have that demon sitting on *my* shoulder too

I don't know how to "flick the switch" at will but it flicks for me every couple of years - the circumstances vary every time but there are one or two consistent things I have noticed. One is that my most successful periods of weight loss typically began with a very small goal - I just decided I was going to lose 4 pounds or so. That meant only confronting a few weeks of restriction and it was easier to face doing - once the pounds started falling away the switch somehow flicked and I was off on a roll, and the 4 turned into 14. So I would suggest forget 18kg - that's too much to face down! How about 4kg, to take you back to where you started? Maybe plan a "feast day" in advance so you have something to look forward to And maybe don't start smack in the middle of winter when we're programmed to hibernate a bit.

The second thing is that for me, it really helps to make a project out of the diet - to set a start date, tell people about it, get some recipes together in advance, go shopping for yummy (healthy) foods I don't normally eat, etc. so that it becomes a bit of a hobby. It helps to plan a reward for a couple of days in - a new piece of clothing perhaps - because those first few days are the toughest. After that, it becomes harder to face quitting and negating the work you have already put in, and when the pounds start to come off it's quite motivating.

The third thing is that I have learned not to beat myself up over setbacks. I used to think I was a useless gluttonous lazy slob with no willpower, but I now know that I am built the same way as most humans and that vast amounts of my brain are designed to make me conserve energy and store as much of it as possible for the future. When I try and consciously restrict food intake, the unconscious parts of my brain start to fight back (the demon on my shoulder etc). There's nothing we can really do about that. So I've taken to regarding setbacks as being periods when my hedonistic unconscious gets let off its leash - aka "mental health days" - and I try not to let them derail me. What happens with me (and probably lots of people) is that these get more and more frequent until eventually I have to accept that I am no longer dieting, and then the cycle begins again. It's annoying to be this way, but I've slowly come to accept it! (One thing I've learned recently is that this "weight cycling" or "yo-yo dieting" doesn't have negative health consequences that anyone has been able to demonstrate - and lots of animals do it - squirrels for example!).

Anyway good luck. Don't lose heart. That switch will flick again but probably when you least expect it. In the meantime, be nice to yourself