Hi, Claire! You'll definitely get the support, encouragement, and advice you're looking for here. You're off to a good start already; you know that crash dieting won't work. I've been going up and down (mostly up) on the scale lately myself and finally came to terms that I had to make a long-term lifestyle change and not rely on temporary diets and pills. It's hard, but once you get started, it really does get easier. I'm almost two months in, and before this, I NEVER worked out. I'd do it for maybe two weeks, tops, before I just gave up. This time around I make a point to exercise at least 5 days out of the week, and it has gotten a little easier. I'm at the point now that if I don't work out, I actually feel guilty!
You say you don't eat particularly badly now; what do you think you're still eating that's bad? What are you willing to cut out or cut down on, food wise? For me it was completely giving up soda, even diet and juice. I also cut out most processed and pre-packaged foods and fast foods. I eat way more fruits and veggies than I have in years. I also started eating breakfast, something I've never done. I'm not a coffee drinker, but I do like my alcohol. I did cut back on that a lot, though. There's a lot more calories in whiskey (my beverage of choice) than you think and it's all empty calories. And I don't ever have just one glass, you know? After realizing all the calories I was putting away just by having a girls' night out, I was able to stop. Right now my body doesn't need those calories, and my losing weight is more important than staying out late with the girls. You have to make the cuts in your diet that you feel are right for you, just know that whatever you don't cut or reduce will have a direct impact on your energy levels and weight loss.
If you haven't done so yet, have a look over on our challenges threads and feel free to join whichever looks interesting. I joined a few as soon as I joined this site and they've been very helpful for me. The girls there are very supportive and motivating and the daily/weekly check ins really make sure I stay on plan. I look forward to reading your successes. Good luck!!