MMOs with group focus and/or group endgame?

Hi guys,

Thanks for taking a few minutes to read this messy post, I really need your help please!

I've been playing around with a lot of different games lately but can't seem to find something that sticks for the moment- so far everything I try is solo casual. I would really like a game with more of a focus on group content whether during leveling or endgame, either is fine. I also don't want to commit/pay only to find out there is no endgame or no grouping or no one even plays.

• F2P, B2P, Sub, anything goes. 
• Trinity or something similar. 
• PvE / PvP or both, does not matter.
• Fantasy preferred but NOT required, anything is fine.
• Some classes I generally like are healers, pet classes, shapeshifters, or something with interesting mechanics. I just mean it goes beyond casting a fireball spell over and over if you get what I'm saying.

Suggest anything, I'm not going to judge anyone over their opinions. Whatever you think fits some of what I'm looking for and providing some info on it would be great! If it's helpful to know I can tell you what I've tried out or played.