... Ive heard of this addon Gladiatorlosa, is that something you guys are familiar with and would recommend? Do you think it would of made a difference if you didn't use it?
Lossa is indeed very good addon.
As for survival, here is one tip:
As a DK you need to be very proactive in terms of survial. Often when you notice things are going wrong, it is already too late.
For instance, against god comp, if you get slienced when devouring plague is already up and mage started pooping on you, it is already late to even trinket and pop AMS.
Start by learning what comes in your way, and learn to pop defensives before the burst hit you.
One trick is when you see a swap on you, always go in Blood Pres and observe the pressure. If you are dipping quickly or healer is being CC'ed, start rolling conversion asap. Store enough RP to keep conversion going and get ready to pop AMS/IBF or spam Death Strike if it becomes really bad.