When a guy has "that friend"

Catharine • There are two ways to behave: as if nothing is a miracle...or as if everything is. -Einstein
I feel like every guy I have dated literally since high school has a friend who "hates" me, usually because HE didn't get me. 
It's not always a friend. Sometimes it's his dad, or another relative. But it's always someone who wants to start rumors and lies about me, or plant the seeds of distrust between us. They say stuff like:
"She only wants you for the money"
"I saw her with another guy" (my brother) 
Or they will just treat me like total crap when my guy is there, say he can do better, and hit on me behind his back. 
Have you ever had a situation like this? How did you deal? (Something like this ended my 8 year marriage so it used to be cute and now it's just very irritating)