While I said "we," I'm coming solely from my own perspective. Though maybe people will be able to relate.
I have noticed that I am not always accurate in my thinking about certain situations. Especially when I'm alone. I over think, worry, and my mind goes to dark places. (I.e. "Why did they do that? Because they dislike me? Did I do something? I did. I suck." Or if I don't feel good about something someone did it could go the other way too: "I'm worried they might be a jerk or abusive"). I have my own special mix of specific thoughts my mind goes to.
Sometimes, its true, I need to be careful with my heart with someone. Other times, I need to slow down, check the facts of what I know about the situation, and if there's things I don't know, do my best to not fill in that blank with an automatic negative thoughts. There are many reasons a person may say or do something. Sometimes, its easy and best to ask why. Other times not.
I'm still working on this.
Just wanted to share.