There can be different reasons why a person has body odor. If you take a shower or bath and wash with lots of (antibacterial) soap such as Dial® and water, use deodorant, and wear clean clothes it is probably not due to poor hygiene.
Bad breath can be caused from certain foods, gum disease, smoking, poor dental care and sometimes it can be a symptom of a medical condition. Treatments often include: brushing your teeth after all meals and before bed, flossing every day, brushing your tongue (especially in the back where bacteria hang out), gargling with mouthwash, eating raw fruits and veggies, and not smoking or using chewing tobacco.
Since you have tried to control both problems without good results, it’s time to make an appointment with your health care provider. It’s important to find out the cause so that the right treatment can be prescribed. Unfortunately, it sounds like your friends have not been very supportive or understanding of your situation. If other people’s comments or behavior toward you are causing you to feel sad, lonely, or angry, it may be helpful to talk to a counselor about the situation.