They lie, they slander, they project.
They say things to make themselves feel better at your expense.
They’re envious and inadequate, cruel. They hate what you do with bitter meanness.
They’re your enemies. If you’re a decent and interesting person, you’ll attract a string of them as you make your way through life. It’s simply human nature.
The specific reasons will vary. Some enemies will flare up because you’re challenging their vested interests, their status quo. Other enemies will be reminded of their renounced ambitions when they encounter your own. Still others will find your achievements humiliating.
Think less of your enemies. Ideally do not give them a second thought. While you may be the target of their anger, you aren’t the true cause.
They don’t hate you. They hate what they’ve allowed themselves to become.