"What's your name?" He had asked, his tone hurried.
"Rose." She was scared.
"'Ello Rose, Run for your life!"
Much later...
"I think you need a Doctor," He said, and kissed her, stealing all the time energy, then putting most back in the TARDIS.
The look on her face when he changed was something that would haunt his dreams for years.
Later...
Rose let go of the bar, and was flung toward the vortex.
"Rose!" He screamed.
Suddenly, a figure appeared, grabbing her, and she was gone. The tear closed, and The Doctor stared into the empty space, trying to keep his composure. His knees finally gave out and he fell down on them, actually crying.
He ran to the TARDIS and after a long while, he managed to get the hologram working.
"Doctor! You're... You're here!" Rose said, tearing up.
"Acually, it's just a hologram. I... need to tell you something." He said.
"W-What is it, Doctor?" Rose asked.
"Rose Tyler," He struggled to keep his voice steady. "I-"
He saw her eyes blink as the world around him started to fade. "Doctor! Doctor, please, don't go! Tell me!"
"Love you." He finally finished, then realized she hadn't heard him. She was gone. "Rose..." He teared, then turned around, seeing Donna, standing there in her wedding dress.
Seeing her again all that time later, and giving her his duplicate, was the hardest thing he had ever done. He had to fight what he wanted so very badly, the only thing he wanted was to kiss her and promise to never leave.
"Doctor..." She had asked.
"Yes?" The Doctor responded.
"When you came here before... What were you going to say to me?" Rose had questioned, looking hopeful.
"I don't know, why don't you tell her?" The Doctor forced a smile, and looked at his duplicate.
The duplicate leaned into Rose's ear and whispered what his original had wanted to tell her for years. "I love you."
She kissed him, and the Doctor hastily walked back to the TARDIS, unable to watch.
After Donna had been returned later that day, he walked back into the TARDIS, looking up at the sky, then allowed himself to cry, slinking down the wall of the TARDIS.
In his vulnerable state, he had fallen in love with Astrid Peth aboard the Titanic, only to have her die... for him.
The Doctor opened his eyes, seeing Scarlett, and held her tightly, whispering in her ear. "Promise you'll never leave me." He said, struggling to keep his voice completely steady.
"I promise." She said, whispering back in his ear.
Then, he remembered, she would eventually die. "'Till death do us part." He joked in her ear.