How do you do it?

I had a random party at Glubal Library and we kept wiping at first boss even though I perma healed (had to, they took lots of damage per AOE). I ran out of MP twice and then couldn´t reboost it (cooldown). The DPS literally stood in every AOE, the rotating stars, the purple stuff, forgot to slide past the book... even though there were no first timers. I had to decide between healing and dodging and in the end they still died, ress, they died again after I healed them up. The first try the tank and I kept trying to get it down in the end, failed because I got stuck inside the book (rip...it´s only my 2nd time too).

I see some healers writing that they live for this kind of situation because it adds suspense to otherwise boring dungeon runs (no sarcasmn here).

How do you keep all party members alive when they are so keen on dying? Will I be able to do this too after 1 year of experience? xD