I would suggest that half a pound, or even a pound either way is not too bad. It's a downward trend that you need.

When I lost weight, I looked on it as an energy balance system. Food in = Energy in. You then have to expend more energy than you put in.
My job in construction was, in theory, quite active. But in practice it was actually fairly sedentary. I drove a lot and I sat in the office a lot. With that lifestyle I found that I could only lose weight if I only had two meals a day. Breakfast of cereal (no sugar) and a cup of tea (also no sugar). That bit wasn't too difficult because I never had sugar with either anyway. I would miss lunch, or just have some fruit. Then in the evening we would have a single course supper of something cooked. If I had a sandwich for lunch I stayed the same weight. If I felt hunger pains, a glass of water was the first choice.
The biggest success in weight loss was going on a fat free diet. This was forced on me, I was not being strong minded or anything virtuous. I was waiting for a gall bladder operation. If I ate fat I was sick and in considerable pain.

But the weight loss was quite dramatic. I had stalled with the slimming and this got me off the plateau.
After the gall bladder I got quite ill and over the next 18 months with other things and I put on some weight; about a half of what I had lost. It was mainly due to some hormone treatment, but also a bit of comfort eating as I was not well and got a bit depressed.
The kickstart to the whole thing was that I was given a routine check by the doctor, who found that my blood pressure was very high. I was given the option of losing weight or taking pills. I chose to try losing weight. The Health Centre organised this. The nurses ran the weight loss bit and I went along every two weeks for a short visit. The frequency of the visits also helped because you had to keep at it and couldn't fast for a couple of days before the weigh-in! Does your doctor/health centre offer this these days? It was cheaper than weight watchers or slimming world, etc.
I started at 115 Kg (18 stone) and got down to a bit less than 85 Kg inside 18 months, which is less than 1 lb/week. Then I got ill and went back up to almost 100 Kg, but I'm now down to 91 Kg (approx 14.5 stone) and I've lost 10 inches off my waist measurement - 48 in down to 38. The other trick is to donate your clothes to a charity shop once it's too big, and get smaller clothes. That way you soon know when you have put on weight, and buying bigger clothes again gets expensive.
Diet is the important bit along with exercise. If you just diet, you will lose muscle as well as fat. The exercise will help you lose the fat only. My diet nurse gave me lots of information and advice on losing weight. She had no axe to grind and no products to sell. She was a bit of a dragon though and she could be qute sarcastic if you didn't seem to be trying...

Keep at it and take a close look at everything you eat. You will probably find that most of it isn't necessary. After two weeks it gets easier. I think that the Slimming World stuff which allows you to eat certain treats is misleading. The energy balance is what you need to look at. Energy/food in = weight gain unless you burn off more than you eat.