1) Have you checked to see how loose the bolt is on the end of the anti-roll bar?
It looks loose in this picture - the rubber bushing doesn't look like it is compressed
2) What made the mark in the muck on the shock?
3) How often do you check your tyre pressures?
It looks like you're running under-inflated...
You might also say that the camber is a bit out the inside of the tyre is wearing a bit more than the outside