My exhusband forged my name on an IRS check return for over $38,000. The bank allowed him to deposit the funds into his solo account and didn't check ID or signatures or anything... can I sue the bank for this money to be returned back to me?

Probably not. Assuming the check was made out to you both, he could have forged your endorsement and the bank would not have had to check more than his ID. I doubt if you can hold the bank liable in this instance.

On the other hand, forgery is a criminal offense. You can report this to the police and have him charged. The court will likely order restitution.

Agreed - you don't sue the bank, you sue your ex-husband.