Heart Broken

I need help. And advice. I feel completely lost and broken. I've been with my bf officially for over a year and a half now. But I lost my virginity to him in high school we were fwb's for four years before our relationship... I went to the obgyn for a yearly exam thought everything was normal. I get a call from the doctors office two days later and I tested positive for chlamydia... I'm scared I won't be able to have children because it can damage your reproductive system. At the very beginning of our relationship I found he slept with another girl so I tried to break up with him but he said he'd change that he couldn't loose me. So I was thinking I've had it since then with no symptoms.. I was so hurt at the fact of thinking I've had it for so long I told him to please be honest was there anything else. He came clean and said he got head from some girl he met at a bar. Maybe three months ago, He tried to say it was because he wasn't in his right mind because he was drunk and had been doing blow. He balled his eyes out for hours and hours I gave him his promise ring back I told him it was over. But he wants to get counseling from our pastor and he really wants to work on things.. Idk what to do anymore. How can I forgive him