In the state your in, even if you cannot accomplish the entire heroic instance. You likely still want to do the bosses you can for points. Also if you feel you are close, I would suggest using consumables if your not, food, potions, scrolls, etc.

Also, if you can clearly identify a Crafted/BoE item that will improve your game as is also worthy of enchanting/geming, I would suggest getting it. Sure it will cost a fortune, but thats just a slot you won't need to worry about for some time now and it might start a whole new world of looting for you.