How do you move on from ex friends and rude people from your highschool?

[neontrees.]

I graduated from highschool 2 years ago and I'm in college now. The people I knew from my highschool are nothing but trouble and want to cause problems with me and other people like the are back in highschool. My ex and I broke up because of childish people like this bothering us about our relationship. Me and him are talking about getting back together but I don't want more people to start drama. His ex girlfriend who tried to be friends with me is a very rude person. She called him up today cursing him and his mother out about why he was even dating me and other people. (She's 20 years old).

I had to delete my facebook and change my number many times because of these people. Whenever I run into these people they just want to act like they are back in highschool again.