Misuse of cheque in case of partnership Cheque got bounced

Hello Sir/Madam, Me and My wife both are partners with equal shares in the partnership firm. The partnership firm started before marriage. My wife has taken around 20 laks from me for personal and company investment before marriage. (I have proof) which is transferred from my account to her account. And she misused the money she has not invested in the company. Now we have some matrimonial dispute and she left me. After leaving me without informing she stolen valuable assets of the company without my knowledge including cheque book. She is not the signing authority. But still she signed a cheque on behalf of the company a taken 5 lacs from local lender. The local lender deposited the cheque and cheque got bounced due to signature mismatch. He sent a legal notice for settlement of the company. I called him i got clear picture that my wife taken money from him. She signed duplicate signature. Now he is asking Me to make payment. Need Legal help.