The kind of lawsuit you are able to file to obtain insurance benefits is different depending upon whether your health insurance is a group policy through your employment or if it is an individual policy.
If your insurance plan is through your employer (or your spouse’s employer), then your claim is governed by the Employee Income Retirement Security Act of 1974, “ERISA”. Your claim is heard by a federal judge, and not a jury. If you prevail, the available remedies are limited to having the judge order the benefit plan to pay the claim and possibly the judge will order the plan to pay your attorney’s fees and costs.
If your insurance plan is individual or through a group association, then you are able to seek many more remedies in either state or federal court and present your case to a jury. Your claim is called “insurance bad faith.” Attorney’s fees may be recovered in some cases and more money damages are available if you prevail. If your insurance policy is through the bogus association described above, you may also have a claim for fraud and punitive damages.