Cheater gave me chlamydia... Trying (and failing) to cope

My ex boyfriend cheated on me before we broke up (3 months ago) and just to be on the safe side I went and got tested. Turns out, I have chlamydia. While it can be cured, this still has been the most horrifying experience of my life, and I have already slept with someone who I REALLY like, but when I told him he wasn't very understanding, and no I'm not sure if he'll ever talk to me again.... Really need some advice on what to do...