I have a fear of vintage clothes why is this? even i think it seems irrational but i can't help it?

There is no "why": You can try to guess why these bother you, but you'll never really get an answer. Dressingup is tied up with emotions, and this is no more or less puzzling than a latex fascination. Online, you can find a video of a man being treated successfully for an overwhelming fear of baked beans. The talk, desensitization, and cognitive restructuring doesn't take long and should free you. Best wishes.