The Vampire Diaries II Damon_Bonnie_Stefan II Familiar Taste of Poison

Okay so basically the first 50 seconds of the video is how the relationship of Bonnie and Stefan started(It's kind of a flashback), but Bonnie is already with Damon. The next clip is of Bonnie and Stefan talking about their relationship with each other and how it isn't fair on Damon and they have a bit of an arguement resulting in Stefan walking away. Meanwhile, Damon is growing suspicious of Bonnie and Stefan's relationship, putting together some things (black & white clips are Damon's memories) and puts together that there is something going on between them. He confronts Bonnie and tells her that whatever she has with Stefan need to end so Bonnie confronts Stefan and tells him just that and walks away leaving Stefan hurt.

Bonnie and Damon then show up at a party together looking happy and Stefan see's get angry/jealous realising that he has lost Bonnie.