Continental Divide Plateau

sandiegocali1

I am 47 and lost about 170 pounds over 1 1/2 year period and kept it off for almost 3 years. During this time, I have tried to get down to my goal of 135 (currently 150) and no matter what I do, it won't budge. i have tried cutting calories, calorie cycling, increasing, low carb, decreasing exercise, you name it. I work out 5 days a week either doing Insanity, elliptical, P90x, walking, anything to try and mix it up and for the past month have increased my calories to about 1750 based on TDEE. Any suggestions, ideas are greatly appreciated.