I never liked the way the scene after the fall of Thessia played out. I always thought that Shepard had to provide some physical comfort to her, especially if she was his love interest. This is my take. It's short but I don't think it needs anything else. Please review!
He stood there, frozen with inaction, clenching his hands into fists before stretching them out over and over again. She typed away at her console, glancing up at the screen with furious determination mixed with panic and complete despair. She was shaking, overcome with grief and shock of what she had just experienced. She had lost her home. Forces beyond her control had suddenly torn every thing familiar in her life away from her. He knew the images of Thessia burning would forever be etched in her mind. Buildings that once stood longer than most civilizations reduced to rubble in an instant, the sound of muffled, terrified screams carrying through the air as they made their way to the Temple of Athame.
The temple. Not only was she witnessing the complete destruction of her home, but she also had to learn that everything she had ever believed in was a total fabrication. Lies built upon more lies formed into the basis of her religion, her ideology, her whole person. He'd taken Javik with him on a whim, and he'd regret it for the rest of his life.
Things like this could break you. He had learned this unfortunate lesson when he was just sixteen. He'd watched the ships descend from the sky and mercenaries pour from their entrances. He ran until his lungs burned and his veins pumped acid through his body. Ran home as fast as he could to get to his family. He found his father first, against the wall of the front foyer with his shotgun still in hand. He'd been able to kill three mercs on the porch before being shot in the chest. His sixteen year old self had pushed the shock of seeing his once strong, proud father dead against the wall to the back of his mind as he followed a trail of destruction within the house. His brother had been shot through his stomach but had managed to kill the fourth merc before succumbing to his own injuries. His body was slumped over his mother, her breathing shallow, her eyes full of fear. Her words "you sister" had been enough to send him running through the burning town with his father's shotgun in his hands, searching desperately for the last member of his family. He found her too.
When it was all over, David Anderson had given him a canteen of water, a blanket, and an unwanted embrace. He had resisted at first, too full of anger and hate to accept any comfort from a total stranger. But Anderson had not let up. He held him there, and Shepard had finally been able to weep for his family. His friends. His home.
He convinced himself that this was what Liara needed. His words were able to break her out of her guilt, his actions had to keep her from shattering entirely. He reached and put a hand on her shoulder and felt her muscles tense immediately. She stopped typing.
"I told you, I need more time." Her words were not cold, only broken.
He only tightened his grip and stepped closer, fighting her reluctance to turn and face him. She wouldn't meet his eyes. He pulled her into his unyielding embrace, and held her tight against him. She was strong, but this was her moment to grieve. He pushed his own emotions down deep inside him for now. He had to be her strong point. Her anchor.
She was silent but she relaxed and wrapped her arms around his waist. It was only when he squeezed her a little tighter in response that she started to sob. He swallowed hard and clenched her jacket as she soaked his shoulder in her despair. Her tears were hot and he could feel his face getting red but he remained silent and steady, offering her the support she required. She was letting everything out, sobbing quietly, shaking softly, and every once and while squeezing Shepard as tight as she was able. When he felt her calming down he loosened his grip a little and placed a long kiss on her forehead.
"If you need anything," He whispered, still holding her, "you let me know."
She sniffled and wiped her eyes, "I know."
He broke away enough so he could look her in her eyes, red and glossy from her tears. He said his next words with unmistakable fury and determination, "Liara. I will kill them all." His jaw clenched. "I promise you."
The look she gave him in return was once of concern…and relief. It was what she needed to hear. It was what he needed to hear.
She nodded her head as he slowly pulled away from her, ensuring that she was ready for him to leave. He saw her mouth the words 'thank you' as the doors hissed shut and he quickly made his way to the elevator, punching the button for his quarters.
As he stepped out of the elevator into his own space he wasn't sure what he was supposed to do next. His mind was pulling his body in a thousand different directions. He made his way to his washroom and turned on the cold-water faucet. He watched the water drain into the sink as his heart rate quickened and he started to lose control.
Thessia had been a complete failure. He lost the data, Kei Leng escaped, and they were now chasing Cerberus, a position he never wanted to find himself in. Thessia had been lost. Perhaps through no fault of his own but it didn't make him feel any better. He had united the Krogan and the Turians, he had negotiated peace between the Geth and the Quarians. He had cured the genophage. He had paid a price for each victory, a friend for each triumph. But this. This was complete and utter failure.
He looked up at himself in the mirror and couldn't recognize the angry thing that stared back at him. He clenched his hand into a fist and slammed it into the mirror without a second thought, without remorse, without feeling the glass cutting through his flesh. He mercilessly struck the mirror over and over as it shattered against the floor. He only stopped when he realized he was pounding his fist into the wall on which the mirror had been mounted and let out a primal, agonizing scream.
He'd lost Thessia. He'd lost Liara's home. If there was one person he felt obligated to personally protect against this war, it was her. No matter how skilled she was in combat, no matter how cold and rigid her demeanor as the shadow broker, he knew that deep down inside she was fragile. Seeing Thessia like that had killed something within her, and that had killed something inside of him.
He went back to Mindoir, where a part of him had died with his parents. He hadn't spoken a word since they had pulled him off his sisters burned body. He looked at Anderson with fierce resolve.
"I'll kill them all." He said calmly. "I promise."