I need to do a better job clarifying. Marauders and juggernauts I struggle with. Marauders have cloak of pain, saber ward, force camo, undying rage. Which are clearly better defensive cooldowns.
Sorry dudeski, its a spec and L2P issue... You are a Sin, a melee/range hybrid. Your bread and butter is melee, but you should play a "cat/mouse DPS" game against this class. Pepper them with ranged attacks, avoid sweep/smash, melee when shroud/cloak is up, stealth, rinse/repeat.
If you are going to engage in melee range, you need to escape/avoid sweeps. You have all the tools to do it. Spec 12 points in the Darkness tree to Disjunction.
If you see the possibilty of one coming:
1. Force Speed
2. Force Shroud
3. Force Stealth
SWeep/Smash is a Force attack, so Shroud nullifies it completely. Speed and stealth nullifies it by making them miss. Stun/KB are also options, but fills resolve, so they should be last option.