The common thing you have to remember for both tanks and healers is that we preform both jobs because we like the classes/roles. There is no glory for tanks and healers. Ever. If things go correctly the DPS will take the credit for a speedy kill. If things go poorly either the tank, healer, or both did not do their job. Never mind that the priority of keeping people alive for me as a tank is healer, then me, then dps. Never mind that they can't do any damage if the tank isn't tanking effectively and the healer isn't keeping the tank alive. Never mind their own incompetence gets them killed 90% of the time.

Tanks and healers are like offensive lineman in football. They make it possible for the quarterbacks and running backs to do awesome things, but no one cares about them until something goes wrong.