Several clinicians are an "in-network" provider with several commercial insurance companies. If you provider is not in your network, she would be more than willing to submit a claim on your behalf.
It is the client's responsibility to pay for any treatment that is not covered by insurance.
All providers accept out of pocket fees (fees vary) for service if you prefer not to go through insurance. Copayments, deductibles, and all other billing can be paid by cash, check, credit cards, or flexible spending accounts.