I was in a couple parties as Paladin today and I'm just confused as to what my role in a party actually is. I know we are supposed to tank but what about the White Magic?

I get people telling me to do all different things, sometimes it's "Heal the rest of us don't just use your White Magic spells on yourself." or "Don't use healing magic, save it for when I run out of MP" and I also got advice from a level 70 Red Mage informing me that "Paladins are expected to only heal themselves."

I usually take in what they have to say take it on board, then when I'm in a different party they tell me I'm playing my job wrong.

So what do you expect of Paladins? Furthermore, Were any of these people wrong/right?