Is it truly possible for a guy to dump a girl because he thinks she's too good for him?

Long story short: Dude is a huge pot dealer. I enjoy pot, but on a social level only. I have a professional 9–5 job that I love. We date for a month and totally fall for each other (before I knew he was a drug dealer). HARD. One day, a “deal” falls through – he freaks out on me, I stand up to him about his bad choices, he ignores me for a week, then emails to apologize and says that I’m too good a person for him and that he just knows I shouldn’t be with a guy who has such a volatile career.

Okay, so obviously we’re over. No question about it – our lifestyles are completely opposite, even though our attraction to one another was magnetic. My questions is – guys, does this happen a lot? I mean, is this a valid reason given the circumstances? Girls, have you ever experienced this? I know this guy really meant what he said about thinking I was “too good for him”, because I could sense that he felt insecure to me the entire time we were dating. I just never thought it’d be reason enough to break up. Especially since he would always reassure me that I was basically the girl of his dreams. I mean, is it really possible to cut out all feeling for a girl at the drop of a hat for this reason?

I know for me – even with all the “bad” things I’ve discovered about this guy – I’m having a really hard time separating my strong feelings from what I know is best. And I just can’t believe that he was able to do that, seemingly so easy.

Sorry for the drama – but I could really use some Fluther advice here because it always snaps me back into reality!