I come from a family with a history of eating disorders (I've never had any, thankfully), so I've always been *very* resistant to dieting. I've never eaten much in the way of fast food or processed food, but I LOVE fancy pastries and scones, and definitely have a sweet tooth. While I've always been active, I'm about 50-60 pounds above my "target" weight for my height, and have been since high school.
About a year and a half ago, I decided that I was going to start getting serious about making changes to lose some weight. Given the family history, I would spend a year exercising more regularly, and see if that made a difference. Although it definitely improved my core fitness and my endurance, I saw little to no impact on the scale. In September, after a convo with my doctor, I started counting calories, and keeping my workouts roughly the same. I've lost 13 pounds so far, which isn't a ton (I've got ~50 to lose), but is still 10% of my body weight!
For me, my goal has been about slowly changing my lifestyle so that the changes really STICK. With that in mind, this is how I've found success:
1. Make exercise social. I'm not a fan of exercising just to exercise, but if I can do it with friends, or do it in a way where I get other benefits (such as seeing beautiful places, meeting new people, etc.) it's much more likely to stick. While I do run once or twice a week on my own, I now do the following:
Mon, Wed, Fri - Rowing at 5am on an intermediate team. Guarantees an hour of solid exercise, and once you're in the boat, there's no backing out! It took a while to get used to getting up at 4:30, but now it means that I get my workout done before I go to work, and I'm not trying to work out in the evenings when I'm already exhausted and hungry.
Sat/Sun - Go hiking, go trailrunning with friends, go snowshoeing, go do trail maintenance, help my mom with gardening, etc. This is usually a high-intensity thing, or an all-day thing.
One other day a week: Go for a run or a walk on my own.
With my family history, exercise used to be about self-punishment and moral virtue -- if I could sweat and grunt and persevere for an hour, I didn't have to like it, but I could consider myself virtuous. This sucked, and made me feel guilty when I didn't go. Doing stuff with friends now makes it so that I WANT to go out, and if I don't, I miss out on a good time.
2. Count calories. I started using MyFitnessPal.com (free! woot!) in September, and it REALLY helped me figure out where I was consuming the most calories, and slowly restructure my diet so I'm eating smaller portions.
A good example: in order to get my day to a good start, I need to eat a good breakfast. It used to be that after rowing, I'd eat two eggs, two pieces of buttered toast, and a cup of coffee. My daily calorie allowance is around 1600 cals, up to 2000 with exercise. That breakfast runs 700-800 cals, easy. That's half my food for the day! Now I eat one egg, one piece of buttered toast, and a cup of coffee.
I'm not anally retentive about counting out what I eat (like, I don't take measuring cups to the cafeteria at work), but I do weigh and measure things out at home, so I'm learning what portions look like. I'm trying to learn what it "feels like" to eat an appropriate amount each day, and it seems to be working. I'm eating less, but not necessarily missing the food.
3. For sweets, test your cravings. I've been playing this game with myself lately -- when I want something sweet, I distract myself for 10-15 minutes with something else. If I'm still craving it, I can indulge. If not, I don't. This worked unbelievably well at the grocery store last week, where I passed by a thing of raw cookie dough next to the eggs. All I could think about was EATING COOKIE DOUGH. I decided to go do my other shopping, and if I still wanted the cookie dough, I could come back for it. Ten minutes later, I was in the checkout line, and realized on my way to the car that I'd forgotten about the cookie dough. Victory!
In the cases where I DO indulge, I try a variation of the trick: try taking half the amount I would before, and then give myself 10-15 mins after I've eaten it to figure out whether I want more. (Knowing the calorie value of sweets ahead of time also helps here.)
Anyway, these are the things that seem to be working for me. Nothing revolutionary, for sure, but effective. Good luck!