The Toxic Double Standard

Let's pretend for a moment, that you're having a conversation with a friend. They tell you that they have a friend/partner/co-worker that is incredibly toxic. This person is unnecessarily cruel, demeaning, disrespectful, and intentionally hurtful towards them. They cause them near constant stress and emotional turmoil. They tell you that they've repeatedly tried to make things work with this person, but it always ends negatively. 
What would you say to your friend? 
More than likely, we would tell them that they need to distance themselves from that person. That they are detrimental to their health and well being and that they would be better off without them. We would encourage them to remove that person from their lives and move on. And we would feel good about telling them that. We would feel like we are offering them useful and worthwhile advice. 
But what if that friend/partner/co-worker was a parent/sibling/relative instead? Would your advice change?
In my experience, when you tell someone that you have removed a toxic family member from your life, you get told things like "You need to forgive and forget." or "But that's your mom/dad/sister/brother/etc. and you only have one." or "That's so sad. You're going to regret that one day." 
Why is it that our standards for acceptable behavior differs from friends to family? Why is it that something we would never or should never tolerate from one group should suddenly be swept under the rug for another? 
Why is family exempt from being held accountable for their actions? Shouldn't people who are supposed to love you unconditionally be held to an even higher standard? 
You would never say to a woman who left an abusive husband that "She's going to regret that someday." so why is it considered acceptable to say that to someone who has left any kind of abusive relationship? 
People who cut ties with family members rarely do so lightly. It's not a decision made in haste and anger. It's more often than not made after many, many years of struggle and heartache. When you feel as though you have run out of options. 
We all have limits and there are some lines that, once crossed, can never be uncrossed. It's not about holding grudges, being immature, or trying to 'rock the boat'. It's about allowing yourself to finally let go of someone who causes you pain. 
People who make the difficult decision to divorce themselves from a toxic person should never be made to feel guilty or ashamed of that choice. There shouldn't be a double standard that makes it ok for some people to hurt you, but wrong for others. 
It is often hard for those outside of the immediate situation to understand the hows and whys, but it is never acceptable to judge them, when you very likely do not know the full story. Even if you have a wonderful relationship with the person they are estranged from, that does not mean that they have the same type of relationship. The husband who beats his wife and children often has friends and family members who adore him. 
Bottom line is this... when someone tells you that they walked away from a painful and toxic relationship, your only response to that should be support and compassion. Regardless of the nature of that relationship. Toxic is toxic. Period.