You don't need someone's acknowledgement for your healing, and others do not need acknowledgment for their own healing.
Forgiveness is tricky, and many people see it as an act you do for others. Nope. It's an act you do for yourself. You forgive yourself for your own part in the situation; you forgive others for yourself and your own healing. Forgiveness is not a statement. It's a state of mind.
In his own recovery (or not, that's his issue) forgiveness for him is whether or not he can forgive himself for the things he's done. It does not depend on you at all. If he's looking for validation, that's his problem.
You're doing what is right for you - you don't have to respond back if you don't feel the need to. I'm kind of with you, as far as the timing of the response goes. I don't think there are many coincidences in life. Just keep going on your path, because it seems to be working very well for you.