Directing is Magical.

Here's a more detailed description of the big climactic scene, and how we shot it:

I sat with my actress, Elizabeth, and reassured her that if she couldn't cry, it would be fine.
She sat there, frustrated, unable to get tears, and I shushed all my crew and had them leave so I could do some one-on-one chatting with her.

I told her that emotional recall was one way she could go about it, or she could do body recall (in which you make your body think you're crying and tears will come). Neither worked. She asked for my iPod to get in the mood. She listened to The Beatles' Blackbird.

I told her we needed to go ahead and do a take, and that she could take all the time she needed, but we needed to go ahead and roll it.

She went through the motions, but couldn't get it.

I went back over to her, and finally hit my directing stride:

"You're the character. You ARE Teresa. You are her. You've lost your brother. He's dead. You thought your best friend had left you. You have no one. You're grieving. You HAVE to let it loose. You HAVE to cry. There's no way that you can move on without letting these tears flow."

I told her that we were gonna do another take, and she could take as long as she wanted again.

She didn't enter the frame for about 3 or 4 minutes. I was worried. I told her to go ahead and enter, and build up more emotions in the frame. She sat down in the frame. She leaned over to the other actress, and sobbed.

It was perfection. We did all the takes while she was crying, and it was magical.

It took nearly 45 minutes to do, but we got perfection from that actress, who I also call my friend.

We all applauded, gave her hugs, and sent her off for about a 15 to 20 minute break.

And that's the magic of movies.