Idk how to feel

I just got told I came back positive for hsv2 and I’ve only ever been with my bf. The relationship is fairly new but we’ve been best friends for 7 years. I just don’t know how to process this, he told me he’d always get tested and that he was clean but he was a bit of a fuckboy in HS. I believed and trusted he told me the truth and right now I’m just in shock?