I had a similar dream years ago where I was at the very top of a giant redwood tree, hundreds of feet in the air, and my friend Neil was up there with me. He was freaking out because he's scared of heights, I thought he was going to make us both fall down. I can't remember what I was doing in my waking life at the time so I'm not sure what it meant exactly.

I guess in your case there could be a connection with the ladder and things are achieving in your life. Perhaps you feel you've accomplished something but you are worried that a friend might spoil it somehow - make you come back down some of the way. Also it could be that you do feel a need for help with your current situation because you're doing more things than you're used to?

It's hard to say without knowing what you're doing in waking life, maybe some of what I wrote makes sense?