I unfriended a racist on FB tonight and it wasn't my sister...
I know she is racist and she's still my sister. I just can't do it even though I know how little she thinks of me. I guess I keep hoping she'll see me differently. She thinks there is something wrong with me and has made some snide comments off and on for a long time. She uses the "N" word regularly. She goes on and on about Obama being Muslim and not being American. She's got every nasty RW talking point. She proclaims her Christianity in one breath and in the next she's as hateful about Obama as I have ever seen her toward another. It's disturbing.
The racist I unfriended was my ex-stepbrother. His father and my mother used to be married to each other. His racism was insidious and it felt like my FB page was getting diseased.
I enjoy the liberal and progressiveness on FB. There are some nice anti-Rmoney/Ryan stuff and it's most certainly not the bulk of the content on FB. I've got some really good stuff that makes FB a decent place.
Plenty of people post some religious stuff, but it's not offensive at all and I don't mind. It's rather pleasant at times.
At least getting rid of some of the negativity might make FB a little more enjoyable.
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Have you thought about filtering your sister's posts into a folder on FB? This way, you can see on the left hand side (under Friends) of your newsfeed whenever there's a post from her, but you don't need to see it if you choose not to do so. I do that for some people I know so I don't get ambushed by some of their politically-inspired posts. 
This way, you wouldn't have to even block her, which would mean she couldn't see your posts, either.
That's a very personal decision. If it comes time to let go, you'll know it. That's up to you. You're obviously doing your best, and you should never regret that.
It's hard. 
It can just be too much work.
I hope your own life brightens with the absence. 
