If you were specifically excluded from your boyfriend's policy, the car would not be covered for the accident you were involved in. As an excluded driver, the insurance policy does not cover you at all when you drive your boyfriend's vehicle.
Being excluded from a vehicle usually involves the policyholder signing a document stating that they agree that none of their insurance coverages will be extended to the excluded driver if that person operates the vehicle.
It is typically the insurer's responsibility to read through the terms of their policy to make sure they understand all aspects of their insurance contract. If there are questions regarding portions of the policy, they need to be asked before it is signed so that situations such as this do not arise and cause the policyholder confusion or difficulties.
Unfortunately if your boyfriend did not ask about listing you as excluded on the policy but signed the form, it is probably too late to do anything about it now, after an accident has taken place with you operating the vehicle.
If your boyfriend needs help regarding the situation, beyond what his insurance company can give him, he may try contacting you state's insurance regulatory body. This state agency usually has a website defining insurance terms as well as a consumer helpline to help one determine if an insurance company is dealing with you fairly.