Like you, I am a young married woman (22 and my husband is 25) who had the same mind set a you. My sexual experience was limited and i was unsure if marriage was right for me. I thought i should be out enjoying life while i was young and free-spirited. My mindset eventually got the best of me, and I cheated on my fiancee 4 months before my wedding day. I could not get rid of the guilt that i had felt and eventually the truth came out, and I have regretted my decision ever since. My fiancee decided to look past my mistake and we got married in July, but my relationship will forever suffer for the mistake I made; we have problems with trust, communication, and intimacy. If i knew then what i know now i would have never went through with it. The cheating was just a mask i used to hide my true feelings, and the problems we were having in our relationship.
I know exactly what you are going through! And i don’t want you to make the same mistake i did because it feels like an easy way out. Get counseling, and communicate how you really feel to him, make him really listen. Don’t throw in the towel just yet.