Receiving harassing emails can be very annoying and alarming. As with any form of harassment, your privacy is violated and you want it to stop. Unfortunately, you can't use technology to preclude man from contacting you via email if they know your electronic mailing address. Although this doesn't mean that there are no solutions to your problem, what it does mean is that there admittedly isn't anything you can do to admittedly stop the man from sending you messages unless you delete your inventory and create a new one.
That said, going through the hassle of deleting your email-account admittedly shouldn't be your first choice, especially when there are other alternatives out there that do work. After all, just because you accumulate a new webmail address doesn't mean that inventory will also not be harassed.