my past PLEASE READ AND COMMENT !!

Okay ladies , I've dated this guy off and on for 3 years he took my virginity 2 years ago ! .. he's cheated , had sex with other girls (even my so called best friend ).. all that . Well I've had my fair share of diff guys & he knows nothing about . Like I've had intercourse with 2 other guys & he still thinks I've been so loyal and never been with anyone els in that way . I'm so scared to tell him . I feel like a whore . I've known both the guys for a while one of them I dated for 2 years (7&8grade) . I've NEVER cheated , but while we was on long enough breaks I did it with someone els and talked to other people . I mean damn I'm 17 years old and we aren't married but like really it haunts me so much and breaks my heart that he thinks I'm some innocent pure girl but I just don't know how to tell him ... he's not the best boyfriend we have our disagreements but I love him . Every time I get around him It makes me upset .. please advice .....