Fiance found out i cheated on him & he is giving me the silent treatment! Advice Needed?

I am 26, American and have recently become engaged to my partner whom i've been with for 3yrs, He is 33 and is from England, I also live there with him. His job has him working many hours including traveling from time to time, at times he always begs me to accompany him, When i met him I was a professional dancer who traveled on world tours and he was so supportive of me. He has a history of being very short fused and confronts people if they say something he doesn't like, but i truly do love him. He has recently found out from a former friend of mine that last year before i quit my job that i had slept with the guy who runs a club in London, I was drunk but i knew what i was doing so i take full responsibility for it, I just never told him as i was sure he would leave me and i love him too much to make the mistake again, I cried alot after and couldn't sleep at night thinking how stupid i was. When my friend said it last week, a fight broke out between them and when i tried talking to him, He just looked at me like i've never seen before, my heart started to race but he just walked away from me. He hasn't spoken to me since and im getting the silent treatment off him, If i try to hug him or hold his hand he walks away from me. He use to be so affectionate, communication was great and our life was seriously amazing, Now at times i catch him just looking at me but not speaking, Last night in bed i snuggled into him & for the first time he held me close to him real tight. My heart is breaking that i've caused him this pain and i swear to god i would never do anything like that to him again, I just want him to forgive me, Any advice?