I used to live in a loft building which had huge double hung windows that you could open. The windows were 89" by 104", huge.

I have heard of people falling out windows because they were fooling around. One of those falls was a guy who lived on the 3rd floor and was sitting in his window sill smoking a cigarette, he lost his balance and fell to the street. It didn't kill him right away but it eventually did.

My point is, no one who is serious about committing suicide is going to jump from the 3rd floor. They are going to want to fall from a distance where it is sure to kill you.

This sounds like she might have been pushed.