That makes you a surety for your friend. And that means you have to take all reasonable steps to make sure she follows all the rules imposed on her as part of her release.
Those rules can be onerous - for example they may say your friend cannot drink. And for someone who is an alcoholic not drinking may be close to impossible.
If you think you cannot make your friend follow the rules you should not be her surety.
Being a surety requires you to make sure the accused attends court as required until the case is over. As mentioned you are also responsible to ensure that the accused abides by the conditions of release. As a surety you are, in a sense, the "jailer" of the accused. You must provide supervision over the accused's daily activities. It's not an easy job.
Should you become a surety and find you no longer can act -- for example you find it too hard -- you can always quit. You have an absolute right to resign as surety and you do not need to give a reason for resigning -- there is a process and you need to let the Court know you are quitting but the process is not complex. But if you do so the accused will likely go back to jail so it's really hard to quit if the accused is a close friend or family.
But if you fail as a surety, in addition to potential criminal liability (which in truth is pretty rare) you can lose the money that you pledged or actually posted on becoming a surety.
This procedure is called estreatment of bail. A forfeiture hearing is held where the surety has an opportunity to show why the money should not be taken.
If you have taken all reasonable steps to make sure the accused follows the terms of release you may avoid penalty. Such steps include informing authorities immediately if the accused absconds or when the apprehension of absconding arises. If you made some, though inadequate, effort to make sure the accused followed release conditions, you may be ordered to pay an amount less than the full amount pledged or posted.
It's a big deal being a surety and you should think about it before agreeing to act and if you act you must take your job seriously.