This girl and i got into a fight now she is trying to be friends..help please?

I didn't know any other way to put the question...so about 2yrs ago this girl and I got into a fight.she started it...the whole reason she was mad is because she was getting kicked out of the apartment and I wasn't.the story is kinda long so ima try and make it short but so you guys understand me.at the time this girl was 17 I think and I had just turned 18.the land lord doesn't like kids under age liven in his apartments with out a parent so that's why she had to leave.me and my boyfriend are living in this place them boom I'm preganent...I have a beautuiful son june 12th of 2010.I haven't talk to this girl in almost 2yrs.now when my son is like 7months this girl is pregant by a guy well she slept with 2 guys so she doesn't know who the daddy is.oh and the guys are brothers so if ones not the dad he is an uncle.I gave her my bas-a-net I wasn't using well actually I gave it to a friend to give it to her.now her baby is born and she is trying to nbe friends with me.why?my boyfriend doesn't like her he doesn't even know I gave her the thingy for her baby.what should I do?why is she trying to be friends with me now after the **** she did?help thanks.