you're right about the omission of information. I think this can be the worse form of lying. In my experience such 'lies' were indicative of a secret life. Far more hurtful.

You're right, the key is acknowledgement. A true apology must acknowledge all aspects of the wrong - not just that it happened but an acknowledgement of your thinking, perception and conclusions at the time. Above all, there must be acknowledgement that you aren't stupid.

A blanket acknowledgement will never release the resentment.

Forgiveness will never happen without that release of resentment.

Forgetting will never happen without forgiveness.

BUT, I personally do not believe that forgetting is always best. I think it does both parties well to remember the transgression. For pushing it back is not only unhealthy but may make the transgression more likely to happen again.