Insecure. Advice?

me and my boyfriend have been together for almost a year now.. im happy with him, we click, and i love him but it's not him im insecure about. it my friends. i know it's weird but that's why i need advice. the problem is, is that they always make jokes about how he looks, or the way he is. for example, im a very short girl. 4'11. my boyfriend, he's not tall at all. more average like 5'7. my friends are those type of girls who only date guys 6ft or taller. and i find that really annoying.. im a big personality person and i saw his personality before his looks. i feel like they don't take my relationship seriously just because of how he looks. i feel like they expect me to be with someone who they see themselves with. they always put him down, saying things like, "he's little. he's not a man he's a boy." "he probably wears an extra small" they even thought i was joking when i said i was dating him. and this makes me very insecure myself. i can't stop thinking about this.. what should i do?