Once, back when I was DBing my then H, he was having a particularly cranky day. I went through all the possible causes in my head - was he thinking about OW and wishing he was with her? Did my butt look fat in those jeans? Was the house not clean enough? I spent the WHOLE DAY twisting and turning myself into a pretzel, trying to guess what the problem was and what might turn him around.
And the very end of the day, as we were in bed getting ready to sleep, he shared that he had an itchy rash on his butt that had been bothering him all day!
Sometimes it's NOT about us, or the relationship, or anything else. Sometimes they just have an itchy butt.