I don't understand the whole space-time fabric thing?

Why would objects warp that invisible "fabric"? that's only possible with gravity on places on earth, not in space. And also, why would the "fabric" be placed at the angle it is for certain things like the sun? Space is 3D so I don't understand the concept of a 2d plane in space and why it would only be placed at a certain angle(the angle that planets orbit)..so confused