Well, he/she isn't banning divorce all together (whatever a "voidable" condition would be). However, this is stupid. Let people get divorced if they want. Why should some return war vet not be allowed to divorce his old wife and marry one that is much younger and wealthier upon his return?
A "void" marriage, as far as I know, would be one that was registered legally but later determined to not be valid -- that is, because one partner was incompetent to enter contract, there was a paperwork screw-up, whatever. This law does seem to ban any valid marriage from ending in divorce.
This is one of those measures I'd be fascinated to see returns on. In fact, comparing this with Prop. 8 returns would be very interesting. But it will almost assuredly not make the ballot, right?