I don't think it's wrong but it's not a kool idea. There are other out there why bother to go through such drama
depends on what kinda break up they had, also what their relationship to you and each is after the breakup... majority of the time it's a bad thing because they will always have those hidden feelings and memories for each other and your best friend might think that you were going after the other person to begin with which is bad just remember that this is a touchy subject and that what ever happens, you have to deal with the consequences, whether they are good or bad
