So sorry you're going through this.
What I can say is that what you're experiencing is very normal. You loved someone, trusted someone, gave yourself to someone, and that person shit all over it. Even worse, your 'friend' did the same thing.
I can relate to your situation because although my WW and I have been married for almost 8 years, she cheated on me just 6 months out from when we first got married (it was an EA & PA, to boot!). However, I never knew about it until 7 years later when I caught her having another affair in 2012. That's when she confessed to the incident 7 years ago.
To be perfectly honest, had I known about what she did to me, to our marriage, back when she first cheated on me 6 months into our marriage, I would have divorced her. I can say that without a doubt in my mind. I KNOW I would have because if you can do that to someone just months out the door from getting married, there are some very serious issues. We also didn't have a big history then, children, etc., so it would have been a lot simpler to cut ties and move on to something more meaningful and 'real'. That being said, now that my WW has started to actually work on her issues, identify the reasons for all the affairs, etc., she is turning into the wife I've always wanted. However, she would not have been able to do that 7 years ago, because she was simply too immature to even 'go there'. That is why I would have simply left the marriage.
I guess you have to look within yourself to see if you really want to stay with your WH and work things out. You're still young, and maybe you don't have children already? And it sounds like your lives aren't really that tied up in one another (e.g., financially, home ownership, etc.). If that's the case, you may be better of cutting ties and really looking for someone who can handle a mature, committed, adult relationship with you. There are plenty of men out there who are fully capable of that. So don't think you're limited in your choices.
Lastly, yes, the innocence is gone. It will never come back. You will never be able to view your marriage with your WH as 'innocent' or something that isn't shared with someone else. That's just the cold hard facts. Everyone on here will tell you the same thing. There is a tarnish on your M that will always be there. Always. It's up to you to decide if that tarnish is a big enough deal or not, and if it isn't, and you truly believe your WH can get his shit together and NEVER do this again, then you can attempt to grow something even better, closer and stronger with him.
Take time to really consider what YOU want (not what he wants, he's already made that clear). Don't rush to any conclusions. Really think about it. Time is on your side. The answer will come to you, I just know it.