Need help with shield grace wp

[Warnoise]

So I am lvl 35 wp grace with stalker set. I have 1H hammer and shield for the sustain. Even though my damage is low, the healing and survivability make up for it when playing solo.

So I reached a point where I kinda have to group up with other players for pvp and dungeons. Long story short the game turned into a humiliation ritual.

In RVR/PVP I felt absolutely useless. Whenever I tried to attack enemies I get either CC'd to death or burst down in a second. My team mates got pissed off at me because I didn't heal them. I really tried but it was difficult because I had to focus on fighting and healing at the same time.

In dungeons, well, nobody accepted me on the team the moment they heard grace wp. I couldn't do a single late game dungeon in my 20+ hour playing this game because I got kicked for not being a healer wp.

So, for the veterans who play grace wp with shield,
I have some questions:

1-In RVR how do you heal your team mates? Do you stay in the back and wait for enemy tank/melee to hit him to trigger heals? Or just join the fray and hit whoever within reach? Personally I found some success by focusing on enemy summons for the heals but it was hit and miss tbh

2-For grace wp with shield, do you build weapon skill and str or focus more on armor and toughness? If there is any recent guide id appreciate it.

3-For PvE dungeons, is grace wp usually considered as healer? DPS? Tank? How do you guys communicate with others about the expectations they should have from you as a grace wp?

When I played salvation wp the game was chill but since I switched to grace with shield it got pretty stressful ngl