Some health plans cover one method, but not another. Maybe if it's too much for you to handle alone, your partner might be willing to split the cost. Some methods seem expensive at first but might be worth the cost for the convenience. Many are funded by government family planning money, and are able to supply birth control at low cost or no cost to women who qualify. A good place to start is your local Planned Parenthood office.
Cost can be a very real factor in deciding which birth control method to use.
Find out all you can before you decide that you can't afford a particular method.