That's a little spooky. Not that there's anything wrong with him being older, just to find out something THAT heavy right before the wedding.
I can see how it threw a kink in things for you. You are certainly handling it well, though. It is disconcerting he could lie to you for that long. But I can't judge; he obviously is a good man to you outside of this because you married him anyway.
I commend you for being mature and forgiving, because this is such a difficult situation. If there is anything I've learned from watching other people's marriages, however, it is... don't punish him for it.
By that, I mean don't make him kiss your backside 24/7 for the next ten years as some means of "making it up to you" or "earning your trust back". Other girls have said, "oh, make him work his butt off to make it up to you so that he knows it isn't okay," but that is a completely unhealthy way of approaching the situation. He obviously knows it isn't okay, or else he wouldn't have gotten nervous and upset over it.
Nothing good ever comes of punishing and controlling your spouse, which is EXACTLY what that is. My ex-brother-in-law did that to my sister when he found out she'd been lying and they were divorced only months later, not because of her lying but because she was sick of him hanging it over her. Every time they got in a fight, he threw it in her face. Every time he asked her to do something she didn't want to, he said she owed it to him because she lied to him. No one wants or deserves to be treated like a dog. Just keep that in mind.
Putting myself in your shoes... I can understand why you're upset. I think my initial reaction would've been "what in the hell did you lie for". But I'm in agreeance with PP, I'd be more dumbfounded than angry and I'd let it go. If that's the worst he can do, then you're doing great.