I know from experience that somehow there is a basic hospitality about me, that emanates from me, that causes some men to construe it as interest, and half the time (or more than half) I don't even realize I'm doing it, and yet after the problem ensues, I start questioning whether I should have tried harder not to cause the problem (I hate blaming myself). I also seethe with rage at the fact that no one seems to have ever taught these men that women can look friendly without the slightest intent of something else.
For example (and this is strictly hypothetical, not based on a true story), I could say in front of a man "Gosh darn it I had such a terrible day today" and put my face in my hands, and yet say the same thing in front of another man and that man may interpret it as an invitation to come over and touch me inappropriately. (Well, in reality I'm not going to do this but I'm just exaggerating to prove a point)
I avoid eye contact with men, don't smile as much as I used to and keep my communication with them to bare minimum. They read it all wrong, they assume we flirt with them because they are so incredibly audacious. Don't trust tem never ever.