I haven't given in, but I have been 2.5 overweight three years now. I'm always on a diet, or thinking about a diet. I lost a stone last year - put it back on. I lost half a stone earlier this year - put it back on. I feel like I am trying to run up a hill and nearly getting to the top then falling all the way down to the bottom and starting again, over and over and over x 100 times.
It would be simpler to kind of give into it and accept this 2.5 stone overweight is actually my new permanent normal. But I don't want to give in yet, but getting rid of it is so very hard. I'll do great for five or six weeks then have a slip or there'll be an occasion I just can't skimp on socially, and I remember how good everything tastes that also puts the weight on, and within weeks I'm back to my old habits.
Also, I was properly slim for around 7 years before this extra 2.5 stone. How did I do it? By only eating the bare minimum and making what I did eat very healthy. So I wasn't unhealthy or starving myself but in reality it means things like: No spontaneous ice-creams in the park, ever. No fast food, or pizza, or takeways, ever. No biscuits with tea, no cake in coffee shops, no chocolate ever, no roast potatoes or Yorkshire puddings or cauliflower cheese if having a roast, no glass of wine of an evening. No cheeky packet of crisps, no picking at leftovers, no treats tossed in the trolley when shopping. All day, every day it's a no for all these things that a lot of people enjoy and feel makes the day go round. That is how (most I'm guessing unless a very high natural metabolism) slim people live. They might occasionally have an ice cream but it would not a typical thing to do even if they make it look natural and everyday. It definitely is not IMHO.
I had masses of willpower back then but it was very hard, but I trained myself to just not eat that stuff and say no all the time. Basically I wanted to be slim more than I wanted to eat the bad/tasty/processed stuff, whereas now my (perimenopausal) willpower is no match for the urge to indulge. I don't like my clothes or body shape much at all though these days.