I am trying to move vertices I select, but suddenly when I hit "g" or drag the move arrows after selecting them, Blender adds a connection to the vertices on the opposite side. This only started happening after I applied a solidify modifier to certain areas of my mesh, but that should not be a problem.
Now I can't edit my mesh at all, since I can't move anything without it drawing weird lines between my mirrored vertices. This did not happen before I applied the "solidify" modifier. But I saved my file, so I can't go back to before I added the modifier. How do I fix this?