Hey what_the_f_man, I'm sorry to hear of your issues with your NAT and connecting to friends at present.
Did you follow all of the steps in our connectivity troubleshooting guide for your platform (PC / PS4 / XB1) in addition to portforwarding? Please be advised that you should not place a PC into the DMZ, though performing that step for a console is fine.
Can you share a screenshot of any error message(s) you're encountering when trying to play or connect with a friend?