Do I break up with him or believe him ?

Hey girls I need help!! So my boyfriend and I are 14 but we have been together for 1 1/2 years. We haven't done anything to serious, even though at times he's tried to pressure me into blowjobs, sex, and eating me out. All of which I have said no to. We go to different schools. Story's have been going round at his school he slept with another girl. 6 people text me today and told me the same. He's cheated on me once before, and I forgave him, but he didn't give me the full story til later on, by then I was honestly like fuck it. One of the people who text me today is a friend but known to make drama, But I believed her when she said he's so different at school compared to when he's with you. He hugs other girls, flirts with them, talks them up. I've heard these rumours before and brought them up but he's always denied them and his mum and family too. But I remember once they made me lie to this chick to protect his sister could this be the same situation? HELP