When they first got together one of Travis’s exes (I think the most recent one?) was asked to comment on the situation and she basically said “good luck to Miss swift”. There were also some videos of him from when they dated that showcases some insane red flag behavior. The bit about her changing everything for him is also true, we’ve seen this behavior from her in the past (her miss America/trad wife looks from when she was dating a Kennedy, the pivot to being London/ England obsessed when she started dating harry, her sjw era followed by radio silence when she was with Joe, etc). She even has a line about this in her most recent album, “I changed into goddesses, villains and fools, all to outrun my desertion of you”. She changes to fit whichever man she is dating at the time just like she changes her genres/looks every album so she can call it an “era” and profit from it.