I am sorry you are going through this. It does sound like you are experiencing a psychological issue. Cheating is certainly not the way to address your Erection problems though. The likelihood is you have associated sex with women with your ED probably through that early experience. Our brains can cause us havoc.
Have you looked at your diet and lifestyle?
By adding a better diet to your life and doing more exercise may help you feel better with yourself and in turn help overcome any psychological factors?
All the best