If you don't tell your husband you had a boyfriend before marriage, is it like cheating on him?

I have been married for about 6 months now. During our courtship, my husband asked me if i had a boyfriend before i met him. I denied it. But now, i have told him that i had a boyfriend long time before i met him. He thinks i'm a liar and i have betrayed his trust. I was just afraid to tell him before and spoil our relationship. Is hiding this fact as bad as cheating on him?