A border is the line between one territory and another. Crossing it is read as a major transition, and being stopped at it as a limit — set by others or by yourself — on how far you may go.
Does the traditional reading fit your dream, or did it mean something else to you?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.