The Theme Of Obsession: Why Did Nina Commit Suicide?

"Obsession is not the same as attachment, it's a mere sense of possessiveness."
"Then are you saying that, my sister was obsessed with me?"
"You could think about it that way, thus to her you were perfect, the only person who acknowledges her"
Laura steps out of the psychologist's office, this is already her third time visiting this place. It's not exactly accurate to say these sessions have helped her in overcoming the pain after losing Nina, but at least they have shed a light of clarity onto what has been before a midst of confusion. Why did Nina commit suicide? This question have wandered around Laura's mind for a month now. She has considered almost every theory possible, depression, bullying, but none quite fit the puzzle pieces together.

For a brief moment I was thrilled and surprised that my sister has managed to get a boyfriend. Subsequently, I took a peek at the tall guy beside her and immediately recognised that face, after all I was waiting for him. I could feel my face darkened with anger, how could Nina out of all people do that to me? * * *
Laura has not yet gotten familiarised with the emptiness burning inside her body each time she is in this room. Between college work and therapy sessions she has barely gotten any time to clean her sister’s bedroom. She had considered keeping everything the way it is but decided that it would just bring her additional pain and agony. She closes the door, determined to start packing tomorrow, though in she knows deep in her subconscious that it will probably be postponed again. Laura returns to her room and starts analysing her therapy session today, desperately looking for an answer to her own question. * *

I can see the library. Laura is standing on the porch with a guy that I don’t know, I do not like him. I run around the building to avoid getting more wet.
“Lau…”
“Your sister is so nice. I swear, mine is like freak. Sometimes I feel like she is controlling even more than my parents. She doesn’t even let go out at night. I…”
I run, as fast as I could, to escape from it, from the truth. I’m sorry Laura, I really didn’t know any of that. I’m sorry.
I don’t know how, but I end up home, in my bed room, alone, with sleeping pills. I call press the call button again, and again. Laura, please don’t leave me, please hurry up, and come find me. Laura, I’m scared. * * *
Today is Laura’s last session at the psychologist. After the last one, she was no longer experiencing anger, Dr Lee said in his email that this was a good symptom, and that I am ready to move onto acceptance.
“Okay then, I think you’re ready”
“Ready for