I'm not sure ECT will scare him away. From what I understand, it's to treat depression, no? He's already claimed to suffer from it so he may not run the other way.
If you're sexually attracted to him, that's tough because it makes it harder to resist, and on so many different accounts, as well. That sucks for you.
Give up on Craigslist! Personal ads generally attract shady people. Oy.
How about trying online dating? You're young. This guy finds you attractive so I'm sure others will, too, and you can try again by meeting someone nice.. at the very least, someone who is "not" a potential serial killer lol