5. Having Absolutely Nothing In Common
If you've been set up by friends on a blind date, that's definitely a situation that could lead to two people having nothing in common and it's excruciating. 

How to conquer this fear: Don't fear it. Lots of people have nothing in common and when that happens, talking about the weather is always your best bet... before you look at your watch and exclaim, "Oh my! It's already 8 p.m.! It's late and I've gotta run!"