Hi, olehcat! I started out about where you are now. I weighed in the mid/high 140s but I'm a couple inches shorter than you. Here's what helped me...
Learned how to eat fewer calories
Over the course of a year and a half, I dropped down to about 107. During that time, I didn't regularly count calories but I did become calorie aware and educated myself about portion sizes. I couldn't believe how many calories I had been wasting on foods and portions that I didn't even really love! I started thinking about the law of diminishing returns in regards to food. That is, I thought, at which point of my servings am I full and no longer getting as much pleasure from my food? And I trained myself to stop eating at the point and save the rest for later. I suppose for many people that's an intuition they've never needed to teach themselves. My intuition, however, had been, this is yum and I'm going to eat as much as I can while it's here. That mind shift helped me a lot.
I also stopped wasting calories on high calorie foods that I didn't love--not worth it. I kept eating high calories foods that I really loved, but I learned less damaging ways to do that. For example, smaller sizes and pairing with low cal healthy foods to fill up on less.
And, important for me, if any food I ate had a lot of sugar or carbs, I paired it with protein or healthy fat to keep my blood sugar even. I never ever ate any sugar by itself, even fruit. If I ate an apple I'd have a serving of cheddar with it; an orange, I'd have some walnuts. Uneven blood sugar makes my appetite insane. I hadn't realized that about myself until that point in my life. That realization was like discovering a cheat. Eating less and healthier became soooo much easier without sugar crashes.
My pairing method worked out so that every time I ate, I was consuming protein and/or good fat.
I became smarter about carbs in general. I'm of Italian and French descent and love pasta and bread. I ate it far less often. I didn't cut it out entirely, but I became more discriminating, decreased the portion size, and paired it.
I found what amount of food was enough to satisfy me and keep my energy up, but not enough to stuff me. I ate again when I became slightly hungry. I never let myself get really hungry because then I'd over consume. (I still over eat if I let my hunger build too much.) I felt like I was eating all the time
, definitely more often than when I was gaining. The difference was I was eating healthier foods and consequently fewer calories at a time.
In the very beginning, I retrained myself as to what a correct portion feels like by eating frozen meals. I ate them most days of the week for a couple of months and always had some fresh veg to go with them.
At nights, if I felt hungry I'd drink tea or eat a big serving of veggies or have some warm milk. If I was still slightly hungry, I'd just go to sleep like that.
Made my diet more nutritious
I researched nutrition and found it fun to work in as many super healthy foods into my diet as I could. My main goal in this regard was improvement, not perfection. Since I hadn't been regularly consuming fruit, for example, my rule became 1 or 2 servings a day (paired with s/t nonsugary). I had always consumed veggies regularly, but I made my portions bigger and ate a larger variety. I started regularly eating good fats like avocados and nuts. I ate more fiber.
Exercise
I briskly walked 3 miles a day. I did that about 4 days a week. That was my only exercise.
Weight Loss, part 2
All of that was what dropped me down to 107ish. I stayed at 107 for over a year, completely content with that weight.
Then I decided to do some more intense exercise. I wanted to tone up. I was curious to see how fit I could get.
Over the course of about 2 months, I dropped another 5 pounds. That speed was rare for me. Along with the exercise, I also counted calories. My goal was not to exceed 1500 a day.
When I stopped exercising as intensely, I gradually gained back the 5 pounds I'd lost. I was ok with that, as I felt like that was too low a weight for me anyway.
Now
Then I had some big life changes and over a six month period gained 8 pounds on top of that. I wasn't cool with that.
I've since lost most of that regain weight but I still have about 3 pounds to go. Right now I'm a size 2 or 4 and 110 pounds.
I've been way too lax with my eating. I used to eat like 80% the way I described above. Now I'm probably at 60%. So I know that's primarily why I regained. I've lost most of it, but I believe the loss has been due to exercise. I need to tweak my eating habits and get them as positive as they had been.