I can't shake off the "thin" image

Most people who know me since I was a child or since college seems to be stuck with the image that I still am a thin guy.  I have gained meat the past 5-10 years that I no longer wear a size small for American sizes and a size medium for Filipino sizes.  So no matter how many times I have told my friends that I no longer fit on a small when we go shopping at GAP or that I now wear a large or even XL when shopping for  clothes back in the Philippines, they still manage to always buy me clothes that are too small.  Recently a friend of mine went home and she was kind enough to get me a T-shirt from the Philippines.  And I have told her several times that I am a large and even an XL back home, she still brought me a size Medium T-shirt.  Of course when I got home and donned the shirt, it was too tight on the arm hole and chest.  Sigh....  It is so frustrating cause I happen to really like the T-shirt she got me.  Now I have to cut the sleeve off and make it a muscle shirt.  And it looked weird after cutting the sleeves.  Even my mom whom I have told many times before she came here to get me an XL shirt from Oxygen and Pennshoppe back in the Philippines still got me size Large shirts.  Of course they were too small when I tried them on.  Everybody still thinks I am this thin guy from 20 years ago.  Really, what does it take to let them realize that I am no longer a thin guy.  Ugh!