Well; firstly choosing to forgive someone cant be defined as — (( I completely agree with whatever mistake you have made; whether your intention was to upset me or not. I will now accept your apology even if it isn't sincere cause Iam a good person; and that’ is what good people are supposed to do )).
Forgiving someone means letting go of the hopeless grudge you are currently holding against them — and moving on with your life. By forgiving someone you actively decide that your time and energy should be spent on more constructive matters; allowing your mind to focus on productive tasks. Therefore; is it wrong not to forgive someone¿ — You decide for yourself.