Xander loses the sight of his second eye as well and doesn`t know how to go on with his life.
Spike shows up at the new WC HQ.
He helps Xander cope ( doesn`t treat him like glas, describes what happens on TV etc)
Think it was Spander.
Xander gets badly hurt while fighting a deamon ( gets thrown in a lamp post?)
Needs a long time to heal ( has amnesia?) and Spike takes him to the mansion and plays nurse maid.