Everyday you are going to meet people, men that you might not be certain of their intention apart from what they say...
As much as it will be unwise to give all a try, I will suggest you narrow your attention to the ones you are interested in...
Even when you meet someone you have interest in, I will suggest that you do not think through the relationship in your head prior to things happening...
Do not create (false) expectations. You already know what happens when you daydream of a family with a guy that hasn't proposed
Trust your instinct at times, and when in doubt- don't
I understand you tell me certain things because you have doubts but there are 3 main reasons I am not in any position to help effectively...
1. Whatever you tell me about the guys is based on your subjective opinion.
2. You usually leave the important details out and that makes it difficult to see the big picture.
3. You never listen
...only when it is convenient for you.
You need to making friends out of the guys you meet. You make a mistake of giving the guy's "titles" like "prospect", "boyfriend", "the one"...
and you relate with them based on those titles
Take [your ex] for instance, he became a boyfriend without being a friend first...
That's why it is difficult for you guys to remain friends when you take the title away
Even the subsequent guys you met, you rather give them double promotion to boyfriend before they become friends...and that's why it's difficult to justify to yourself why you should consider them
So when you meet a guy, before you grant them titles please make them friends first