Being the only Heavy in a group
Sounds like you almost should retrait when you are looking at tanking. Also use your CC that you can (slow and immobilize are your friend), and there is nothing wrong with stepping back to stay alive and heal up even if a squishy gets downed.
Heal on crit food – it’s your friend. Also that’s why PVT gear is bad, go for Power\Precision\Toughness to be tanky.
And don’t be shy to disengage, kite and dodge. Light classes can and should be able to survive some hits, giving you time to heal up.
If they got self-support then direct mobs at them.
and they expect me to seemingly melee when im the only one and they dont use support on me, since most light class support must be used on themselvs to live, I always end up dying.
then they are a bad group and you shouldnt jsut blindly obey to them, but do waht you can to survive and help the group (and you rarely help the group by tanking in melee 24/7)
And this is coming from someone with a thief that i built a little too squishy for my own taste, and is trying to redo a bit, and a mesmer as my lvl 80’s even and i would never expect the only warrior in my party to be able to melee all the time