Long story short, my SO was out of the country for a week last month, and it turned out to be the worst week of my life. He casually mentioned plans to go for another trip soon, and my thought process immediately turned into a giant minefield. 

My brain basically translated his comment about enjoying a week or two overseas into "I would love to get out of your presence for an extended period of time!" and "Yes, that's right! Because you're so annoying and I can't wait to be free from you!" It then turned into "Yes, I know it will put you through hell but I'm going to dump you in it anyway. Because I don't love you enough to care about your pain." 

Whenever he falls silent or doesn't reply me immediately, I start wondering "Why isn't he saying anything? Is he frustrated and trying to compose himself? Is he exasperated and thinking wtf not this shit again? I'm annoying him, aren't I? He's not going to want me anymore!!! What do I do???"

I explained this to him, and while he was extremely supportive and validating, it was clear that he was also very perplexed. And I guess it just hit me that regular people don't have thoughts like these; they don't live in constant fear of abandonment. How nice :( anyone else have any other examples?