Forget to forgive

I've recently lost myself amongst my own thoughts and previous events, but was struck by confusion when I thought back to times when I have accepted apologies, despite their lack of integrity. I'm confused as to why, as human beings, we feel obligied to accept apologies just because we have been asked for forgiveness. It seems no matter the measure of damage caused, if someone apologises, you best accept or be considered careless and selfish. Well so what if looking out for your feelings is selfish? I'm sorry for being human and wanting to keep my heart unharmed, and please diregard any obligation to accept that :)