Well first off I recommend that you not be so hard on your friend. There are sooo many people that have it and that doesn't mean that she did something bad to get it. The most common ways to get it are thru kissing and sexual contact. However it can be transmitted thru saliva to the mucous membranes (eyes, nose, mouth). Since it can be transmitted this way, technically you can get it from eating or drinking. Its not a big deal really. She could have also got it from her mother at birth. It may seem gross to you because it really has gotten a bad rep. It's not a pleasant thing to get but it's also not the end of the world. You should be supportive of your friend, she's going to need it as you guys get into highschool.