The Brilliant Mind Frustration

He decided to leave Passadena and go back to Texas. He packed his suitcase and said goodbyes to the guys. He said he would come back after couple of weeks. Leonard knew something was wrong because his eye twitched but didn't ask anything. He really didn't care about it right now. He was still too shocked to function normally.

Penny had died. His girlfriend, Penny. Their neighbor Penny. She was gone.

Sheldon knew there was a social protocol saying that one should stand by his friends side in grief. But there were enough people to comfort Leonard right now: Raj, Howard, Bernadette and Penny's sister. And Sheldon had to get out of Pasadena before the aching in his heart became irreversible.
He had tried everything that was in his power. He hadn't slept for 3 days searching for possibilities how to help Penny who was lying lifeless on the hospital bed. He read the newest research papers about head injuries. Turning every page he was hoping to find a cure on the next. He spent hours on phone with the best doctors from all over the world trying to talk them into taking of this hopeless case. When one of them agreed to operate Penny, Sheldon went home,took a shower and fell asleep as soon as his head touched the pillow. Dr. Shephard flow in in 14 hours from Heidelberg. Penny's heart failed.

When Dr. Shephard walked down the hallway of the hospital and stopped in front of Leonard his eyes fixed on the floor, Sheldon felt a small twitch in the middle of his heart. He could never read emotions well, but after eliminating all for this situation unfitting possibilities, he was left with disappointment and symphaty on Doctor's face.
"I am sorry. Her heart was to weak. "- Dr. Shepherd said placing his hand on Leonard's shoulder.
First he heard Leonard breaking into sobs as Penny's sister held him. Then Sheldon's knees felt like jelly and he went down to sit on the floor holding his knees tight at his chest.

He didn't know what was the social protocol in this case. He had never lost someone before who was that close to him. His father died, but he was very young and could barely remember. Sheldon thought this new feeling in the core of his heart would leave but days went on and it didn't. It got stronger every time he passed the door of 4A. Only then he realised how much of his time Penny took. How many evenings they used to spend together and how enjoyable those evenings were. The thoughts made his heart warm but the numb aching never faded away. He was feeling so helpless for not being able to erase this aching from his heart. He was angry for not being able to help Penny. He knew all about stars,. planets and galaxies, their shapes and sizes, but now every time he looked up at the sky, he thought how small and insignificant he was. Sheldon hated it. He hated everything about it. He hated himself. Soon he didn't find any joy in his job and left Cal-Tech.

Sheldon Cooper took the train to Texas.

After 19 years:

It was springtime. The wind was frosty but yet pleasant. Sheldon Cooper was standing in cemetery in front of a gravestone. His brow was knitted as if he was remembering something. A smirk lit up his face. He kneeled and placed a small teddy bear on the grave.

"Daddy, can we go, please ? I want an ice ceam! " – a little girl about four run over to Sheldon and stopped before the gravestone.
She looked at the inscription on the gravestone and read it out loud.
"P. . . E. .NN . .Y."

She tugged at Sheldon's trousers.
"Who was she ?" she asked looking up at Sheldon.
"A very good friend of mine." Sheldon replied his eyes still fixed on the gravestone.

"She has the same name as me." the little girl remarked after a littla pause.

"She does, indeed" Sheldon smiled and touched Penny's nose with his finger. He took her in his arms and they left the cemetery.