Does the female of the species have to wear a dress to a wedding?

[autodidact]

If so, is there any dress that would be flattering for someone shortish, very buxom (shapely but huge breasts), horrid postnatal belly, good lower legs, the rest non-descript, a not fat but could afford to lose a few pounds and tone up a bit size 12? I really find it hard to find dresses that look good. If not, what other garb would be acceptable? I always manage to look wrong at weddings... Please help!

I can never tell the difference between a tunic and a dress. What is it?

Tunic - Usually has elbow length sleeves or longer and is long enough to cover a tummy and a bottom but it will just skim the bottom, so really not long enough to be a dress (unless you want to display your sunshine to the world).

Lots of people wore trouser suits to my wedding. I did get married in a hot pink ballgown though, so I think people guessed it was a bit more 'relaxed' than your typical affair