Your BMI is 33, putting you in the obese weight category (BMI >30). If you've tried diets and exercises in the past and have failed to keep your weight off, then you may want to explore weight-loss surgery and see if it is right for you.
Recently the FDA approved the LAP-BAND from Allergan for people who have 30lbs or more to lose, a BMI of 30-40, and at least one comorbidity (such as asthma, diabetes, or hypertension). You can read about this in my sharepost: http://www.healthcentral.com/obesity/c/276918/138712/comorbidity-loss
Good luck with whatever you decide to do!