Need help in boasting my confidence..?

when i was in my high school, I was flirt and was easily gullible. People around me use to think that I am flirt and they used to hate me. Now after 10 years, all this things har me. I am getting married soon, I am commited to this guy since 6 years now...I am scared, that if he comes to know about my past, he will feel bad about me?