As described in the Star Trek books "Time for Yesterday" and "The Vulcan Academy Murders" (both TOS), when a bonding is broken, it is easy for Vulcans to die from the shock unless they have other family members around to support them.
This is also evidenced in the Memory Beta wiki as well as other writeups in various places. However, in the Star Trek (2009) movie, when Amanda is killed, Sarek merely walks off of the platform.
Is this a plot incontinuity, or is there another explanation?