Just send 1 satoshi to your own bitcoin address (or to mine) without any fee. That will stop you from gambling at least for a few days. 
How would sending one satoshi help?
It will lock your funds till it gets 1 confirmation. You have to send from the address which you have to lock.
You will get it unlocked in a few days. (Don't blame me if it takes forever.)
Hardly foolproof. Most people have more than one address so they might have to send many satoshis, but this wont really stop a gambler anyway as the desperate ones will just buy more or find a way around it.