Same for me. A pen is like a foreign object now. Everything I try to do with one ends up looking like
garbage since I can't cut/paste or fiddle with the spacing or composition.

For me it's simply because I've barely touched a pencil in three years and now it's almost alien to me.
As for advice I'd say just keep hammering away at it. Like any wall it will break eventually if you
bang your head against it long enough.