Through your mentality, you will be alone. There's nothing wrong with not wanting to shack up with someone, but there is a problem with the way you left dude hanging. I don't care if you bought him a hot meal after work, the fact that you, in your own words, "Chunked him the deuce" is immature and cold-hearted. It's more important to take into consideration the context of you doing so. When he had everything "together" you were fine with him, but as soon as he fell on hard times you left him. That is why you will be alone.
As far as your take on dating:
The 1st scenario is what's called a "fuck buddy". They are not a dating partner. I'm sorry, but someone you date you have potential interest in. Even with a fuck buddy, you don't "chunk 'em the deuce" when you find that they hit upon hard times because there's a mutual understanding that you only are together to chill, have fun and fuck. So there is no reason to abandon that relationship unless you get tired of fucking them...
The 2nd scenario is a bit better, but your thinkin' is still convoluted. You say that the person has the potential to be really special but yet in your definition of dating vs. being together with someone you opt to talk to other people. The saying, "Don't put all your eggs into one basket" can be applied, but when it comes to people that's just insecurity. Playing the field means that you haven't found someone special or even remotely special. So if you are talking to someone that has the potential to be special in your life, it might be sound and good judgment to treat that person accordingly.
These two scenarios alone with what was mentioned prior is why I think you will have a very hard time finding someone, and if you do, you will eventually be lonely if your mentality stays the same.
Did this broad just say "This is my thread". 
