Forgiveness requiring an apology isn't true forgiveness, it's more akin to revenge.

And if you wait for an apology, you'll never be able to forgive, remove that burden from yourself, from those who have wronged you who are dead. Many instances of anger and a lack of forgiveness are multi-generational - or even parent/child.

People can rightly forgive without the other party even knowing about it. In fact, I'd argue the best kind of forgiveness is done completely silently, personally, and the only way anyone could figure you that you have forgiven someone is through your subsequent behavior.