Excessive rear tire wear

Hey whats up everyone,

I'm new here, and i have a question...I was in tahoe last weekend and i lost a tire while i was driving. It turns out that the insides of my rear tires had completely worn down. Its like the allingnment was extremely off, however it was on the rear. The car was not in 4WD. I was thinking i could change the rear shocks and see what it did. If anyone has suggestions that would be awesome. thanks.

-Wesley