A Good guy.A cheater.And no self control?

I broke up with my boyfriend of three years last night because he came forward about cheating. I could not understand why! He was not the "type" to cheat. He always respected me.He was the biggest sweetheart,gentleman,and he always wanted the best for me.I thought he was perfection.And I guess my problem was that I assumed he was perfect and put him up on a pedestal.I have been with several jerks who cheated and this is by far the most shocking.Just the last thing I expected from him. After him constantly beating himself up about how he could just throw everything we had away and not even being able to answer himself why he did it...he finally became honest with himself.We had agreed to save sex for marriage. He had done it in the past, but he wanted to save it for me.or someone.But we did engage in other sexual activities.Then I went away for college last year. We had visits twice a month,and everything was working out great.The last time he visited was in April..and we had sex for the first time.And maybe thats what sparked it. He said he has dealt with these sexual urges before(which im sure all guys do?) but never acted on in it.Then he said one day the urge just overcame him and he gave in to a girl(who just so happens to have wanted to sabotage us from the beginning.the fact he is oblivious to that is aggravating!) he knew would give him oral.(sorry for being crude). My first reaction is..um why cant you use your hand!? And he said it was just the idea of the act..not a particular person..that got to him.Obviously the man I looked up to as being so mature, was in fact very immature when it comes to his body.So here is this very "good" guy. who made a very bad choice. And I ended it because I knew if it happened one...although his remorse..it could probably happen again. And I couldnt understand if I was in his heart,how this could happen. I love him, but I think I made the right choice,right?Everyone so far has told me that cheating is a deal breaker.no second chances.and once a cheater always a cheater. He made me very happy,but this tore me up.The hardest part and maybe the silliest part for me to get over is just the fact that another girl touched him and he felt good by her.Are there any encouraging words to help me get over that?!please.And I guess I feel kind of used as well.(which is why I shouldnt get so serious so young)We are only 20. Is this something he will grow out of?He knew it was wrong.To me its as simple as knowing its wrong and loving someone else to make it easy just to say no.Am I right on this?. I want him to make good choices in the future.Also, I still love him.Of course I do.And he says he loves me.Moving on from this is not going to be easy at all..Please be respectful in your insight. Im going through a rough time,obviously.