The duty of good faith and fair dealing is generally owed by the insurance company to its insured, not to third parties. This means that your insurance company owes a duty to your spouse - not to you. Unless you are the beneficiary of the insurance policy payments (like in the case of a life insurance policy), you generally cannot sue for bad faith. There may, however, be some limited exceptions.
Making Bad Faith Claims: the Duty of Good Faith and Fair Dealing
Because you buy insurance before you need it, by definition, it is important that your insurance company is actually there for you when the time does come for you to make a claim. As such, the law imposes an implied duty of good faith and fair dealing on every insurance company. This duty mandates that the insurance company not deny claims or refuse to pay out if the claims are covered by the insurance policy. If an insurer refuses to pay a claim that is obviously covered, then the insured who paid the premiums may be able to sue and collect damages.
However, this right generally refers to the right of the insured who has the contract, since the relationship is between those two parties. Third parties to any contract usually do not have the legal right to enforce contract provisions, nor does the duty of good faith extend to them, because there is no "privity of contract." The only exception that allows a third party to enforce a contract is when the contract is made for his or her benefit, such as in the case of life insurance.
Getting Help - Bad Faith Claims Against an Insurance Company
There may also be exceptions if the insurance company's refusal to pay results in your spouse's death or incapacitation, such as if he doesn't get the necessary treatment due to the health insurer's refusal to pay. To get help determining whether or not you might have a bad faith claim, consult an experienced lawyer as soon as possible.