Hi. I would start with telling your boyfriend clearly that his remarks are making you insecure. If you are close with your friends, let them know too. It seems like they don't realize how much they're hurting you. Know that you are not any single piece of your anatomy. You are so much more than a body. You are all your experiences and dreams and likes and dislikes and goals and family and friends and you are so much more than your appearance or your teeth. I recommend checking out beauty redefined on instagram. They are great.

I'm so sorry to hear that. No matter how "playful" they are saying this it's not right thing to do. They should have some empathy and realize how horrible that must feel for you. I hope you can find friends who don't judge you like that , not even behind the courtain of "joke". I was bullied a lot and those things..they really leave mark on you. I don't wish that not even to the worst enemy. People can be so shallow pointing out at others criticizing them only to appear and feel better about themselves. Know that those people they aren't all humanity and that if you dare to make new friends eventually you will find those who won't judge you and will enjoy your presence. I also know it can be hard to do so but there is hope and escape from such destiny.
Part of how beautiful you are depends on how beautiful you feel. So of course if everyone around you is making fun of your apperance you will also unknowingly give vibe of lacking confidence which is super important for being perceived as beautiful. A lot of times personality can overcome outside look in terms of attractiveness and just general perception of good look. Especially if you are confident and funny. Try to break this cycle of not feeling pretty enough !