STD advice

So I been seeing this guy and I got tested about a week ago and my doctor called me and told me I have chlamydia... I’m usually careful but have had my fair share of condom breaks before him and with him Im not sure who gave who the std and I’m mortified to ask him if he’s been recently tested and if he’s slept with anyone before or during me without a condom and I’m honestly nervous to tell him about the chlamydia thing.... how do I tell him and I personally feel he’s the one who infected me so I don’t wanna come off as blaming him but I’m always careful and get tested once every three months like doctors recommend and this was my first check up in four months.. I don’t wanna leave him or have him leave me cuz he thinks I’m sloppy or something so I just need some real advice talk