how to tell him....

How should I tell him I have an STD I know I got it from him. And idk if he knows what it is but thinking on it now I think he knows but didn't tell me. I didn't see it at first and then one day I noticed it when he actually trimmed everything for once and asked him about it and he said idk what that is it's been there for 11 years or so been to the doctor not for that tho but they never said anything about it when they seen it. Idk how to feel about it either to be honest I didn't have sex until I 19 and I with that guy for 7 years and then I had one Bf for a month and nothing and have been with him ever since we're getting married in a few months and idk I feel like I tried so hard to pick the right people made a lot of hard choices to keep this from happening and boom the girl that got made fun of and called names because I wasn't sleeping around or doing what the cool kids did still got what she was trying so desperately not to!!!! I feel kinda lost and dirty. 
He didn't cheat it really has been there and I have read and talk to my doctor HPV doesn't lay doormat it's like herps it only happens if there is conctact with it. The virus itself never goes away but you can remove the warts and things just like any other wart but it could come
Back or never come back unless you come across someone else that wasn't treated. So basically if you see no warts it can't be spread even if you have the viruse.