AN:

Merry Christmas everyone! Here's the first of my two updates for today. I'll be updating again, some six or seven hours from now.
Same goes for tomorrow So safe travels and I hope you don't get bored!

Right, so, when accompanied by a spirit, the 'dark' Morgana we know is written in italic font.

Aglain's appearance and disappearance had left Morgana more than a bit shaken. Three spirits, he had said. What on earth had she been drinking?
She was no farther from the door than she was when the impossible druid was there, which meant it wasn't a dream. She tried to shake off the feeling of dead and believe that it had all been part of her imagination.

There were more pressing concerns such as the manservant in chains. She laid a hand on his cheek and let one of her nails roughly scratch the surface.
She wanted to scratch his eyes out so he would see the darkness she had been living in for so long.
Why not put him in chains? From her point of view, he had done more wrong than good. Right from the start, saving Arthur was a mistake. He should've let him die and Uther would have had no choice but to publicly announce that she was his daughter and heir to the throne. Time and again he risked his life for him but only once for her. She trusted him and he didn't trust her back. Once had she shown him the truth behind the mask and he betrayed her as if it meant nothing, as if Gwen or Arthur were as close to her heart as he was.

He was special to her and she couldn't keep inside the single tear ran down her cheek. She hated him for what he had done to her.

The sound of a snapping twig pulled her attention away from Merlin. A quick peek through the window revealed a shady figure collecting firewood.
The witch did not trust anyone who would dare tread so close to her hovel, her refuge from madness. She was outside in an instant and did not care about the snow ruining the rag she called a dress.
"Who are you!" She demanded to know and for the second time, her heart jumped.
In the streets of Camelot, he was nobody but your average commoner. This was the spirit of a man long gone. He had passed on to the next world or so she thought.
Nevertheless, she called the dark skinned man by his name "Tom?"
"Hello again, Morgana." He didn't sound as upbeat as he used to be but slightly distracted like when she and Gwen passed him by while he worked the forge.
His demeanour could hardly be a surprise considering he was dead.
"You're dead." Morgana frowned and backed away.
"I am the Ghost of Christmas Past." He explained calmly and she was everything but calm.
"Don't you dare come even near me!" She was trying to bluff her way out of it.
He was a ghost and she hadn't the faintest clue how to deal with such a creature. She turned around and sought refuge in her hovel from the nightmare but it only got worse.

She rushed through the door and found herself in the castle of Camelot.

She looked behind her and saw that Tom standing by the door.
"Why did you bring me here?" She demanded to know.
An ear-piecing scream alerted her of a presence but she did not expect to see herself.
They were in the chambers of the Lady of Camelot and Morgana saw herself sitting, crying and gasping for air from the strain of the nightmare that had passed.
"They can't see us." Said Tom as Gwen walked over to her mistress.
"You're safe, nothing can harm you now." Gwen tried to comfort the distressed Lady of Camelot.
"It was awful." Morgana averted her gaze in disgust as her other self wept.

Time sped up, a magical marvel in Morgana's opinion and possibly the only thing on the journey worthy of appreciation. Then time slowed down once more and just in time for the sun to shine through the window and shed light on her bed.

Morgana was looking at her dresses and wondered if she should procure another such fine a thing. The witch could not help but silently admit to herself she missed that.
Gwen entered the room being incredibly cheery and carrying flowers.
"Someone's brought you flowers." She sang as she moved over to the Lady of Camelot.
"Was it Merlin again?" Morgana asked softly as she took the bouquet from her hands and smelled it. The witch's stomach twisted and turned.
"Need you even ask?" Gwen said and if it wasn't for the flowers, the maidservant would've seen her mistress blush furiously.
"What's the point of this?" Morgana asked coldly.

Arthur blundered into the room in his rude and regular fashion of not knocking.
"Gwen, did you see Merlin?" He asked.
"He was here a few minutes ago."
Arthur frown and was about to leave when he noticed something and reopened the door.
"Did he give you those?" The Prince nodded towards the flowers.
Morgana scoffed at the remark. "They're from an admirer. If you wonder what it's like, grow up and stop abusing the servants."
"I already have one." He cooed with a very short glimpse towards
Morgana's eyes turned towards the heavens and moaned "Kill me now."
"Just the one?" She teased.
The Prince rolled his eyes and left.

Morgana frowned at Tom.
"What do you see when you look at her?" He asked.
When Morgana refused to answer, he continued. "I see a young woman with a heart filled with hopes and dreams. She had friends like family. She stood up for the less fortunate, anyone who couldn't defend themselves. Despite the setbacks she was a strong woman to remain so hopeful."
Of course that wasn't what Morgana saw "No, she was a naive girl. Uther would never change, never did. If she were strong, she would've killed Uther."
Tom half-closed his eyes and continued "You tried avenging me but backed out at the last moment because you cared for him and didn't want Arthur to live without a father."
"Like I said, she was weak." Morgana bit back.
"You were strong." Tom dared to defy her. "It is easy to hate the world but it takes strength to forgive."
Morgana turned her head away and refused to answer any more questions, it was pointless.
"Come." He said as he opened the door. "I have one last thing to show you."
The door that should have led to the corridor revealed stairs instead. With great hesitation Morgana walked down the steps.

They were in the burial vaults where Merlin beseeched her to stop the undead assault on Camelot.
"We can find another way." He pleaded.
The story played out much like she had remembered until the point where she was knocked unconscious by debris.
She didn't see Merlin's eyes glow gold and neither did she hear the spell. She watched him as he destroyed the staff with his sword.
He moved towards her, sword in hand, and Morgana feared for her life.
She was lying there unconscious, something to be associated with the meddlesome manservant.
Morgana came to her senses that this was the past and she was still alive, he hadn't harmed her. She remained silent to watch the past unfold before her eyes.

He kneeled besides her and laid a hand on her cheek. Merlin ran his thumb across her cheekbones. Morgana involuntarily put her hand on her cheek as if she could feel his touch. There were tears in his eyes.
"Is there no other way?" His voice croaked. He should have known that her heart wouldn't change a second time. He should have killed her then. The ordeal with Alator wasn't the first opportunity he had to kill her. There had been others but he apparently he never could bring himself to kill her.
"It's all my fault." He was crying even though she was neither dead nor dying. "I should have told you. Things would have been different if I told you."
If he told her what? Oddly enough she found herself hoping desperately. The witch tried to supress the feelings that rose in her chest but it was already in her heart. Doubt seeped through the cracks in the ice.

But it was the past, she couldn't change it. Whatever secret he kept then would no longer matter. They were enemies now, plain and simple.

In the blink of an eye she was home again.

AN:

Out of all the deceased, I think Tom best embodies the time Morgana was still good.
Confronting Morgana with Gorlois and/or Vivienne would be too extreme, they might actually hold too much sway over her.
Uther and Morgause were possibilities but they hold too much personal interest. Uther would only look at his son and Morgause would never want Morgana to give up.
Therefor I chose Tom, the father of her best friend before her first attempt on Uther's life.