7 Segment LED reverse voltage problem

Correct.
It's a component with 5V at both electrodes.
A diode with the anode at +5 and the cathode at +5.
A diode with the anode at +5, the cathode connected to a resistor, and the other end of the resistor at +5.
What's the voltage across? 0V

(NB A resistor is required between each segment/LED and each output pin. You could get by with one resistor in the "CA" line, but you'd have to make certain that only one segment would be on at a time. Stay with a resistor for each until, for now.)