Here's the thing, you suck. My Mar can practically solo most flashpoints minus the bosses and larger pulls. Get better at pulling and keeping the pace moving.
I've actually spent a good deal of time keeping my gear updated with mk-9 augment slots with the current level augment. I usually have more health than your average tank by a fair amount. Most players neglect their stats. Hell the other day, I was literally in a fp where the tank had zero mods/enh/armoring. Thankfully my merc healer is geared and I carried the pos.