I had lost all of the weight that I wanted to (1994), then starting around 1999 my weight began creeping up to 30 pounds over where I wanted it to be.
I tried everything I could come up with -- went back to induction levels, various supplements, coconut oil, lots of exercising, etc., etc. It was extremely frustrating, and I was quite unhappy with the situation.
I do not think that our bodies are best at a weight significantly higher than the standards (i.e., I'm 5'7", 130 is a really good weight for me -- you're 5'4", you would likely do very well around 120 pounds) -- and unless you're a body-builder, I seriously doubt that exercising is causing a huge muscle-weight gain. Also, I am 60 years old -- aging does not mean that your body should weigh more!
Anyway, last Christmas I happened to read a newspaper article about a supplement called hoodia. Decided to give it a try. And over the New Year's I carefully evaluated what I was eating, what the problem could be, etc. I decided that the only thing I hadn't really tried was to cut calories.
Starting January 1, I seriously cut my caloric intake (using the hoodia, an appetite suppressant -- something that worked for me). I planned my meals so that I was getting optimal nutrition with minimal calories -- and it worked! At all times I adhered to low-carb, and whenever I checked, I was in ketosis.
I lost 1.5-2 pounds per week, and got down to 130 pounds -- where I am happy to be. I am healthy, my muscle tone is quite good (I'm far more limber and have more stamina than many of the young people I work with) -- I found that as I lost weight my exercises became easier and I could do more -- the extra weight was making moves like bending over far more difficult than they are when there's no belly interfering!
I would suggest that you keep trying tweaks until you find just what works for you (for me, it was the hoodia with a carefully-planned low-calorie/low-carb diet) -- it is so much fun to be able to walk the beach for 5 miles (without getting tired -- and in a bathing suit, not a tent!), roller-blade again, bike for as long as I want, buy size 6 pants (!!!), etc., etc.