I feel like I could take bits from everything you've all said and it's be like I wrote it!
I've distanced myself from sooo many people over the years because I've just got so sick of the one sided-ness of friendships. One group stopped inviting me out because I got a boyfriend (now husband). I was fully available but they just didn't want to know anymore. One friend I'd known for 8 years and who was meant to be my maid of honour made EVERYTHING about her. She had 2 years to plan it and 1.5 months before we were due to do something, nothing had still been organised for my hen. More recently, some friends when asking how I was after each of my miscarriages, I wouldn't actually get a response, or the conversation would change immediately to some mundane shite. It was clearly just to look like they gave a fuck but didn't want to launch into their problems without an opening.
I very swiftly drop all these people with no regrets. I'm such an agony aunt and would sit on the phone at 3am listening to drunken ramblings or rants about 'i had sex with some boy now he won't text back' or 'my husband cares more about football than me' but it is physically impossible to get any kind of respect or care in return.
Anyway, that's a long story but the crux is, fuck them. Its blunt but you'd rather have strangers on the internet who give a shit about you, than not getting any love from people you've known for years. It hurts too much and you're worth so much more!