advice please

angel1984

My ex wife and I, had a joint loan which we both pay half for, after getting getting divorce, she wanted to see if we could reclaim the PPI we had taken out on the loan, I said fine, my ex wife got the forms and I signed the form to start the proceeding with the bank, since then I heard nothing back from her

I went into the bank to see what was happening over a month later and if we had been successful and to my horror I found that the bank had given back over £8000 into our joint account, my ex had changed the billing address of the bank so I wouldn't find out and then my ex wife had withdrew all the money, the same day, claiming the money was in there I should of checked, so the next day she took it all out of our existing joint account which we hadnt close and into her private one.....
My understanding is I can prove that I paid half of the loan ( using bank statements) and the account is still in both our names(the balance is zero) , so I should be entitled to half of the PPI refund as well.

ive asked for half the PPI back as im entilted to it and she says i wont get a penny, my next step is a small claims court isnt it ? or at least threatened her with one??

please help...........