@roughtim,
Google how to block a number on your particular brand and model of phone. Delete her contact info, and have any emails go to spam. Unfriend and block her on Facebook, don't follow her on Twitter or Instagram, etc.
If she still manages to get through to you, tell her you're not interested. Slam the door in her face if you have to; tell your wife and have her do it, whatever.
Say
no and mean it.