Falling back into love with my first love. Is this wrong?

Some people are gluttons for punishment. You were off and on since you were 18 but you fell in love with another guy. What makes you think you won't do that again? What makes you think he won't stay with his current girlfriend? What makes you think he deserves you after what you pulled? I've been in the same shoes as him sister...theres a reason why someone is your ex....and it's usually better that it stays that way. Sounds to me like you know you really screwed up and want to try a second go at it...I feel sorry for him if he feels the same way.