Crazy ex wife. What to do?

I have been with my boyfriend for four years now, and his ex is always haring us. If it isn't one thing it is another. Now she is on this kick that we are drug dealers and do drugs, because we won guns. My boyfriend is a avid hunter, and she knows this. But she is calling the cops on us. WE DON'T DO DRUGS. She is very snaky too, she won't come here and har us, she only does it on the phone. What can I do. After four years of being called a slut, , drug dealer, alcoholic...etc. I am at my wits end. There are three children involved, and I swear we never ever do anything to put them in danger, she is CRAZY. She isn't happy unless she is complaining about something. Can I press charges? Is this Slander?