Dad's are supposed to be honest, but supportive, not hurtful. So he wouldn't be doing you any favors by saying, "Oh, you're beautiful dear." and letting you go to the prom. Imagine the embarrassment there when the clasp broke, so he did kind of spare you that fate. It could have been better put, as in, "The dress is beautiful dear, but maybe a bit too tight, you might want to re-think the size." Same message, just a little more gentle than the punch to the face your dad served up. Take the good from the bad, your dad was looking out for you, in his own twisted sort of way.

Hey you're from Alaska so you must be an Eskimo and they are usually chubby, and a lot of guys like chubby girls, it's just more of you too love!

Fatherly Advice. Always Listen!

Ignore the size number next time and buy what fits. But since daddy could have been a bit more tactful have him pay for the new dress.

Even if your father has a genuine concern about your weight (which may or may not be legitimate; obviously no one here knows what OP weighs or how she is built), there are less hurtful ways that he could have said it. That being said, even a person who is a perfectly healthy weight will not look good in clothing that's too small. (It doesn't help that the sizing of most women's clothing is pretty arbitrary and varies by manufacturer.) Perhaps he just meant that the dress was too small? Granted, there were still much less offensive ways for him to have conveyed this.

Next time by the size that fits perfectly, maybe your dad wasn't trying to hurt you on purpose, but was trying to give you some fatherly advice.

Father knows best

At least he was honest? It doesn't do to lie to yourself, ya know.

When guys comment on clothes, I find it's usually true because usually, they don't care. Especially if it's from your dad and he's usually not a prick, it usually is coming from a loving place,..that, and he probably pre-weakened your clasp.

Who cares what ppl think. Everyone is beautiful no matter what. So your clasp broke. Fix it.