Coins don't exist. It's just pixels. She can't take pixels from him.
It's like stealing pictures. Same thing.
He can move the coins to another wallet. Leave 10-20 BTC on the wallet he was using before.
Then he can tell to that bitch : "Here's your half"
OR,
like someone else mentioned. He can say that he got them by gambling.
First , the OP is a troll. Second....
Same with bank accounts.
They are numbers on a piece of paper.
The privatekeys are associated with addresses had hold an amount of BTC , valued at: x.
Divide x by two and problems solved.
Or do you think that the judge is calculating the amount of wood and paint in a picture and not the value at which that painting can be sold on the market?