Yes, that is normal, you will not get an apology. Even if you reconcile you may never get one. Your husband is not unique in this regard, the spouse who has the affair does not apologize, and asking for an apology will make them angry.
If you Google for "affair recovery" you can research what you're going through and what to expect. Those sites will explain what he is thinking and why he won't apologize. Just know this -- he does feel badly and he feels guilty. He's ignoring you because he doesn't want to feel that way -- no one would.
That is why you detach and GAL, if you fix yourself and find peace, then he is able to approach you without feeling horrible guilt because you no longer seem devastated. Make sense? Easy to read, hard to do, but that's the only thing that might work. Pursuing or seeking admission of guilt or an apology never works, and has the opposite effect of what you want.
Accuray
Married 18, Together 20, Now Divorced M: 48, W: 50, D: 18, S: 16, D: 12 Bomb Dropped (EA, D): 7/13/11 Start Reconcile: 8/15/11 Bomb Dropped (EA, D): 5/1/2014 (Divorced) In a New Relationship: 3/2015