Hi kaynah,

You can say it to whoever you believe as God, or to Nature, or to the Universe, or to Life, or to the Source of Creation, or to your own self, or simply in the air to nobody. If images or thoughts of the other person are coming to the mind then you can mentally say it to that person too. Nothing to worry about getting it right or wrong. Simply say it mentally or loudly to whomsoever you want. But don’t go to that person and say in front of them directly/verbally :),although you can say it mentally when they are with you.

Regards,
VJ