在愛情的世界里， 不被愛的才是第三者。
When it comes to love, the third party is the one who isn’t loved.

~ 犀利人妻第10集貼士 The Fierce Wife, Episode 10
I came across the quote (that’s my English translation) while watching episode 10 of Taiwanese idol drama The Fierce Wife and thought it offered some food for thought.
Is it right to say that it doesn’t matter who came first? What if the second was THE ONE? Is there such a thing as ‘responsibility’ towards the one who came first?
I say it’s best to let the person go if his/her heart isn’t with you any more. There’s no point hanging on to someone if he/she is with you out of obligation or a sense of responsibility. It’s like two birds trapped in a cage. Why not set the two of you free and go on to soar on your journeys? I think that’s a better solution than being with someone who doesn’t love you, no?