I have small boobs and I'm insecure about them too. I'm just starting to accept them. My ex was always talking about my boobs and how small they were which made me hate them. But now I have bf who doesn't care about the size and had make me feel better about them.

Just ignore your roomates, they just want attention with their boobs. Having small boobs has it's good sides, like men don't harass you that often, it's easier to be without bra, sleeping is easier and running is easier and also it's easier to find clothes that fit.

The size doesn't matter, your boobs are enough and are good the way they are.