Damon had been undergoing a lot of stress lately. And whenever he was stressed, it usually endangered the lives of poor humans. After meeting Stefan and Elena (indirectly though) he was troubled by memories of their past with Katherine threatening to sneak into his thoughts again. 

He had been trying hard to control the blood lust and stop killing innocent people for Melanie's sake but was constantly failing to do so. Even though Melanie had grown up and was a lot mature now but still this has always been a sensitive topic for her. 

Seeing the least bit of blood or wounds made her unstable as her past was tainted with dreadfully painful memories. So Damon was trying his best not to give her any reason to go through all the trauma again. 

A few days back when he had been suffering from one of his depressing anger fits again, he had left the house to go to a nearby bar but she had followed and seen him draining the life out of a poor innocent human. 

Since then she was in a pathetic state. She had become terribly silent and would spent most of the time oblivious to the world staring out of the window or at the ceiling. He had never wanted her to see his true side due to the effect it could cause on her. 

All day and all night he would see her going through the daily routine works as a mechanical robot and it hurt him that the once bubbly chatterbox Melanie had grown painfully silent because of him. 

Damon was unnecessarily soft with her but it could not remove the dreadful scene from her mind. He promised her to retain his self control and do his best to avoid killing humans. She was acting so weird since that day and it hurt him. 

But his promise was also a difficult one to keep. For a vampire who has fed off of human blood for centuries it was literally impossible to switch on to animal blood and as a result he was weak, starving and with a continuous burning sensation in his throat. 

He knew it wasn't long before he would lose his control again. And in that case it was a great threat to Melanie. Whenever he was close to her or made any physical contact with her (intentionally or unintentionally) a searing pain would course through his veins and it became almost impossible to hold himself back. 

He feared if he lost it and she got hurt. He knew he won't be able to forgive himself if it happened.

He stepped into the living room to find her in  the same position as he had left her about two hours ago; staring absently head of her. He sucked in his breath trying to shut out the scent of her blood. 

"Damon," all of a sudden she spoke causing him to stop in his tracks and turn around to face her after taking several deep breaths to calm himself down. 

She had spoken at last after many days.  She was still staring ahead mindlessly but there was something different; she wasn't scared instead her face appeared to be eloquently sad, "I miss him. Please bring Stefan back." 

He suppressed the rage that had shot through him, "I suppose we were clear on that. You promised not to mention... him... ever again." 

She let out a soft sad sigh, "Damon please. I need him." 

He spoke through gritted teeth but the pitch of his voice was rising, "I told you every single thing, Mel. I can't forget the past. All that has happened to me, all that I have been through is because of him." 

His breathing was turning unnatural and he had gripped the table so hard that his knuckles had gone white. She stood up and was now standing right in front of him but he took a step back. 

"I know but Stefan is part of our family. Without him we are incomplete. You must realize that we both need him as much as he needs us. And even though you don't show it, I know you miss him too," she tried to convince him. 

He was in a terrible state and even though he knew she was right still he chose to neglect the truth, "I don't need anyone! I don't give a damn about him!" 

He was about to leave but she placed her hand on his arm to stop him, "no, you do. You still care for him." 

He stiffened at her touch, "Don't...Touch...Me." 

She was taken aback by his words and a blank expression crossed her features, "what?" 

He released the breath he had been holding, "stay away from me." 

She looked in his eyes which were darkening, "is that a threat? Are you threatening me?" 

He was constantly clenching and uncleching his fist, "yes. You will not ever mention Stefan again. Stop looking for him, stop waiting for him to come home. Just stop!" 

Her eyes sparked rebelliously, "or else?" 

He certainly didn't want to enter into an argument with her especially not now, "Melanie, he is not coming back, do you get it? Because he finally found his happy ending. He is not coming back and I will make sure of it." 

She lost her outward calm, "no. You can't just order me about as if you own me. I'm not going to obey your stupid set of rules this once because you're wrong. I want him back so I'll bring him back and if you have any problem then I'll leave." 

He grabbed her arm forcefully to stop her, "you are not going anywhere." 

She pulled herself roughly away from him, "yes I am. And you're not going to stop me. You can't." 

He shot her a warning look, "Mel... don't you dare... leave me." 

She ignored him and proceeded towards the door. She knew Damon had just blown up everything and it was the right thing to leave him and seek out Stefan so they could help Damon out. She had Stefan's contact and she was sure he would help her bringing Damon back to his old awesome self. 

She didn't hate him but had to give him the impression so that he could let her go. But she wasn't expecting what happened next. She had unlocked the door but in a flash Damon had slammed it shut again. 

She felt Damon's hands on her neck and felt everything go out of focus. Her eyes blurred as she tried to breath. She grabbed his hands but couldn't move them. In a second he had forced her to the wall opposite the door. 

His eyes were piercing right into hers and her breath hitched in her throat as she saw him baring his fangs. His voice was choked, "I warned you not to do that." 

She couldn't register fully what was happening. Her legs seemed to collapse underneath her and she felt drained out. She was on the brink of passing out when he let her go. 

She fell gasping to the floor. Her head was whirling and she was still trying to figure out what had just happened. And the next moment, everything lapsed into darkness as she fell unconscious.