She was your girlfriend for 3 years as you two went to the same college and are neighbors...not only that the both of you are childhood friends

One day she got invited to a play by one of the boys at the acting club..you were suspicious at first but you let it go..after a few months you can't keep it on because you saw how he looked at her..and sometimes caresses her arm and holding her close..she was oblivious about his intention as you approach her and told her to quit the play and stuff as she got mad

"W-what you mean by that!..this is my career y'know how much I wanted to be an actor jealous of him! Me and him are nothing!.. whatever..we are over if you like this*

After the two of you are over it's been a few days as she over heard them.. saying how the plan is effective and soon she be his..and she can't believe she was a fool and ran away to you trying to find you