They are dumping you!
It doesn't matter how nice they are about it or how they choose to get the message across to you, they are still telling you to get out of their lives.
Now, I understand how painful it can be to hear that someone doesn't want you around, especially if you have a long history together, but whining about it will not change their view about the matter... especially if you choose to whine to them. Telling them that they are wrong isn't going to change it, in fact it will more than likely just piss them off. Stalking them on their social media sites will very likely end with a restraining order.
And here's the real bugger of the whole thing, I don't know how to get over being dumped any better than anyone else. All I know to do is cut them out of my life as completely as I can, talk to the people who do love me and do want me around, and sooth myself as best I can with happy things.