When somebody deliberately sets out to do you emotional, physical or financial harm, you must classify them an "enemy".
Moreover, you MUST have a measured response. People make choices every day; they exercise their freewill. When they know what they are doing is harmful to you, yet they do it anyway? Well, it is time to roll up your sleeves and strike back 10 times worse.
Personally, I can't wait to get my revenge. . . I'm salivating just thinking about it