I have bad teeth no matter what i do to try to improve it. why could this be?

ACIDS: If you are doing everything right yet getting cavities all the time, you may have acidic environment in your mouth. Most common is acid reflux. Have your doctor check this. High stress reduce the protective saliva flow, so stress reduction is important. How is your food? Eating healthful, fresh food is also important. Low exposure to Fluoride when young may also be why. You'll then need fluoride.

Are you...: Are you brushing 2x/day for 2 full minutes by the clock? Are you flossing daily? Do you use a fluoridated toothpaste, mouthwashes? Have you reduced sugars, starches, acids in your diet? Have you had a recent Physical exam with your MD/DO to check for systemic causes? Do you see your Dentist as often as he/she recommends for care and treatment? Call your Dentist.