There’s two variants. One is extremely harmless and is generally oral. This is the one that nearly everyone has and no one really notices. The other variant is generally genital (though either one can be in either place) and is more severe and less common. The first outbreak can be really bad, subsequent ones less so. An estimated 1 in 10 adults in the US have it, though I’d imagine it skews a lot more towards highly sexually active communities. It can be transmitted even if you don’t actively have sores, though that’s much rather. Condoms also don’t prevent transmission, though again they make it much more unlikely. While getting it certainly doesn’t have to be the end of the world it is worse than they generally say.