Attention-seeking friend?

So I have this friend in our clique who is somewhat an attention seeker. Let's call her M. I love her because she's my friend but her "attention-seeking" antics annoy me. For example, in school, she would talk and laugh in a really loud voice... curse loudly at other people... talk back to teachers (call me old-fashioned but my family taught me that younger people should respect older people, so yeah)... speak obnoxiously during class... brag about how she lost her virginity at 14 to every girl she meets (She recently befriended my old friend who is really cool and all and I was shocked when M told me that my old friend was shocked when she found out that M already lost her virginity at age... I mean, do she really need to go brag to people like that?) ... and sometimes humiliate others in front of many people. I sometimes think she do these things to act "cool" and stuff. One more thing, she saw a picture of my friends in my old school and she asked me if we get bullied before because they looked like losers.. I was really hurt at her comment. Help?