So...we are probably all aware of the difference between fact and opinion. But how many of us here are anxious about something that isn't a fact, just an opinion? A fact is something that's driven by rational thought, is undisputed and has supporting evidence. Whereas an opinion is reinforced by emotion, and based on a belief or a personal view.
For example you're walking down the street and you see someone you know. They don't talk to you, don't look at you, don't talk to you. So instantly, you presume that she hates you, she's being rude, snotty, she doesn't want to talk to you, someone must have said something mean about you to her...etc, etc, you can probably all imagine the mindset in this hypothetical situation.
When the only facts here are that 1)She was on the same street as you 2)You know her and 3)She didn't talk you, for whatever reason.
Why she didn't talk to you could have been for various reasons. She might not have seen you, for example, and well, you didn't exactly say hi yourself and make your presence known, did you? (Heck, we've all done it...well I have anyway, anxiety and all =/ )