You could even tell her about your own past mistakes (or invent some stories) like "oh this one guy convinced me to do this and this with him and he just made me feel like I was really immature if I didn't, so I just ended up doing it, then he dumped me the next day for this girl in the grade above him. I felt so stupid and embarrassed about the whole thing, and then all his friends started calling me a ****."
That's a bit dramatic, but you get what I mean. If you talk about these real experiences it will just sink in more.