Hmmm, since it's coming out of your paycheck his side will figure it out sooner or later. Someone will notice the missing $ from a total, OR see a pay stub and ask where that $ is going.
If you don't have a lawyer then perhaps you can use that $ for their retainer. They can't claim half of what isn't in the account.
If he spent a bunch of money on stuff and ran up debt today, you'd be responsible for half of it.