Blocked, from the back?

Ok, here's a fun one for you. I had an idea. I know, it happens to us all, but this one decided to throw me through a loop.The story began at the end, as in I know how it will end. I know the faces, the place, the twists and the dialogue. I didn't have a beginning, so I just let it run and there ya go. I started writing the story, and the first few thousand words or so worked for me, the story flowed quite well.
But now.....I seem to have found a fork in the literary road, and the signs are both blank. I know where I need to go, and I sort of know where I started from....but I don't know any of the terrain between. I want to write, I need to write...but it feels like I'm forcing it, and that just causes a worse block.

So, in conclusion,

HELP!?!?

Sincerely,
Stuck.

Ty. I've tried the diagram before, but unfortunately it only proved to sidetrack me more. I haven't tried the "write to" points though. Or, rather, I have them in my head but don't know how to put them down on paper. Part of the problem is that I am a natural editor, which puts pressure on my flow. Of course, when I write something and feel that I just don't like it.....I want to rethink it, but I leave it alone until I'm done, then I'll go back over it.

Since I already have the end of the book fully laid out in my head, should I go ahead and put it down? I have the (forgive the redundancy) beginning of the beginning. Would having the beginning and the ending down help filling in the middle?

I'll give that a try. Right about now, I'm willing to try many things. The characters are getting angry at me.

A novel is the intended goal, and I've already surpassed what could be considered a short story.

Sent

Got it, and thank you

Well, it's helping already. Thoughts are coalescing into finer points and tomorrow I will begin setting up "Write To" points and designing Acts. Those suggestions definitely helped my train of thought and may just get the ball rolling again.

So again, thank you!