Love like mad (twilight and TVD)

there was a lot of things that happened on TVD but what you didn't know was that Kathrine had a identical twin sister who went through everything with her. She helped Kathrine with a lot of thing but it got to the point were she couldn't take being overshadowed as the second choice to Kathrine. That was until an old friend of hers sister calls her saying Edward was going to kill himself, so she had no choice but to help her stop him. Little did she know while she was there 2 people would find a mate in her.