I agree with the others, that giving others our medications is a dangerous thing to do. On the other hand how easy it would be to give to our friends.
I never had a problem with using birth control pills. I gave birth to three live babies, and one miscarriage. I took birth control pills to gain weight, but never had to use them for birth control. I know how hard it has to be for your friend.
I hope your friend will seek help from her doctor, or change her doctors if he/she is not meeting her needs.