There is something you aren't doing correctly. You may need to get some help. I used the doctor at triforlife.net. In 1.5 years I went from 260 to 137 and I have a new life.
you need to learn to modifiy your workout..after a while the body gets used to the same old routine..sometimes a break from the workhout helps. I know ive went through that many times..now i workout in the mornings, instead of the evenings..have to give your body a change of pace otherwise it will platoo and it wont burn as it should.