1) OCs are in love with someone, and their relationship can either be picture perfect or end with holes in the wall. They fight with each other, lie to each other, etc but they still can't get enough of each other so they never break up. 

2) OCs have close friends but when it comes to OCs being able to be popular or in another cliche, they change who they are to try and fit into this new crowd. OCs old friends are a bit annoyed and distance themselves before going off. 

3-A) Flame and your OC have been friends since they were kids, but with high school comes new things; Relationships, clubs, new friends, and people trying to be the most popular. Flame falls down the hole, changing who she is to try and get more attention. Meanwhile, your OC is left in the dust, trying to hang onto their best friend.  

3-B) Like 3-A, just reversed.