Re: Is this a venous leak? What's going on?
After reading your post I thought of some issues that you did not cover. Around the time when the ED started did you begin taking any medications, either prescribed or OTC, change medications, change diet, start taking "power drinks" or other stuff now being advertised for muscle enhancement, hurt yourself around the groin area - even something you considered minor at the time, move to another location, change jobs or had some form of bad employment related or social experience. Did you want to break off that relationship? It seems strange that a woman would walk out on someone she loves just because of 4 months of ED problems. Women are usually pretty understanding about those issues.
I'm no expert on this subject but I do know that, absent any physical disabilities - which you do not appear to have - sex is all in the head. Just a passing thought of something you forgot to do can ruin an erection and a lot of things have to come together to keep the male process going often enough and long enough to have a satisfying sex life. Also, consider other factors in your life - the death or illness of a relative or close friend or the general lousy state of the economy if your job may be on the line. Depression that you might not recognize (or ignore) can also cause ED problems and so can the drugs used to treat it. Don't sit around waiting for a urologist to give you an answer. You'll probably come out clean anyway. He can force you to get an erection with drugs and determine how long it lasts. If you can physically perform, that's it. You will be back into psychology again.
Be kind to yourself and don't push yourself into performance anxiety by trying and failing on a daily basis. Give your body enough time to perform on its own. Your Testosterone and Semen production continue on their own without your help to the point where you can't stop a spontaneous ejaculation. Wait until just before that happens and then try masturbating again. If that works your self-esteem may begin to increase to the point where you can increase the frequency.
All of the above is purely layman's advice given without any research other than my own practical experience.