One way to overcome this social anxiety is to learn how to relax in these situations. There are many relaxation techniques that you could learn such as deep breathing, guided imagery or progressive relaxation. You could teach yourself by buying a self-help book or audiotape, which are sold in many major bookstores. There are also many forms of relaxation that are taught in the class format like Yoga, Tai Chi and meditation.
If you have tried some of these techniques without success, you may want to check and see if there are any socialization groups being offered in your area. These groups offer a safe and supportive environment while you learn to cope with your nervousness. If no groups are available then maybe you should consider seeing a therapist who has experience dealing with anxiety disorders.
Many people suffer from various forms of anxiety, but with some work and determination they usually are able to overcome it. Sometimes people that suffer from nervousness and anxiety need to get professional help using a mental health therapist. If you live in northern New Jersey, you can contact Atlantic Behavioral Health's Access line at 888.247.1400.