Are you sure they were all wallets and not just empty receiving adresses? If you use a wallet with changing receiving adresses, the old ones will remain 'active' but it will always show new adresses, wich all link to the same wallet. It's just so you can give out a new adress to each customer, to check theyre payments etc.
Well Basically , all those wallets had money , then I sent money from each one of them to this 1 wallet (that didn't dissapeare).
once I received all the money on this one wallet , I closed Multibit
after few days , I opened it back and all the adresses with 0$ dissapeared , only the one that had money didn't
and I'am pretty sure they were wallets
what could they be other then that . I clicked "New Wallet" to make them.