Another thought on backstabbing...

I learned this the hard way, back in the days of political infighting at work -- trusting too quickly and too easily will result in injury. Since I'm a truster by nature, I've acquired scars from the inevitable stroke that falls when I'm not looking. On the other hand, even if I haven't learned to prevent such attacks, I have learned to survive them. You might get me once in the back, but you'll have to offer further attacks to my face.

And what about the one who was my pal? The one I let in, the trusted one, once he or she has revealed a proclivity for the cheap shot -- what then? Why naturally, trust is revoked, forever.

If it happens once, shame on you. If it happens twice, shame on me.