Frustrated with not losing weight?

It could be lots of things, but try this... read about cortisol on the internet. If you get too much cortisol (which can occur when working out at a high intensity) it triggers your body to save your fat! It is a fight or flight mechanism and it thinks all that sudden exercise is because of some crises, so it is saving up your fat for later... Instead of your hard-core long workouts, try going for a nice brisk walk for a half hour in the morning and add a little yoga or pilates a couple times a week. I'll bet you'll find your body responds much better- I hope.