I recently returned home from a business trip to find a hair tie in my bf's bed that wasn't mine. Once I noticed it, my bf quickly tried to explain it away (he just moved, the movers could have packed it, he was sloppy in cleaning up ex girlfriends stuff, etc). Ironically when I went downstairs, he immediately changed the sheets and the hair tie disappeared. Seems suspicious to me; I know these things just don't appear. There are no female relatives around. We just started dating (two months) but he made it clear to me that we were exclusive. My gut tells me that something was going on; my heart wants to believe otherwise.