You got to sit and watch the damage be done, unable to do anything, and now, you have the power to keep it from happening again, but restricted from doing so in order to keep your partner happy.

If that person ever sees this, they'll know exactly who and what I'm talking about.

To make them happy, you have to bite your tongue and pretend they are tolerable, but you would want nothing more than for them to feel what they inflicted on your love. To show them that this person wanted to even be with you and show you how you can be, only for you to betray them.

Now picture that you two are finally together after years, and the first one tries to come back into their life. You can't stand this person's very existence, but because your now partner wants to still be friends with them, you refuse to let them forget how they hurt the one you love.