Product: Credit card or prepaid card

I received an email alert regarding a change on my credit report. 
Apparently, there was some application for a credit card, in which I did not fill out. In addition, my account had been locked, permanently and I don't know how this is still happening. Most importantly, I could really use your help, as my husband and I had to close our checking account ( that very quickly went from over 100k to XXXX in a few months ). While SOME of this, was indeed us, we definitely did not spend all THAT money. It mostly went to household expenses and also payment for my XXXX XXXX treatment, above what my insurance pays, a far cry from XXXX. 
As of last week, {$0.00}. Also last week, I'd deposited over 10k. There is something extremely strange happening. One of the charges on my card linked to my checking account, for example, had a number on my statement. It was from the previous day, which was last week for an order. I know and knew for a 100 % fact, that I did not purchase anything that week. And, I don't purchase from that company. And, to add more info, the card it was charged on was a card that was deactivated due to previous fraud. It makes no sense to me how an old card that is supposed to not work, was able to get into my account. I told the representative what was going on and who I was. She asked me my name, number and address, to which I complied. She told me she did not have anything in my name or with my checking account debit card. I then told her that the charge was in fact from a now deactivated card due to fraud, that had been deactivated some time ago. Good thing I kept it because I had all of the numbers. The representative told me the name that was used for the order happened to be a name that I knew. It was " XXXX XXXX XXXX ''. This was my old married name **over** a decade ago. The email address she gave me I have never heard of! Over the past few months, I thought everything was getting low due to my illness however it disappeared practically overnight and I really don't know why. There are a bunch of charges that don't belong to me. But they somehow have my information. Also, I don't want you to believe I didn't make charges myself because I did as well as my husband. However there are many that we can not explain. It's at the point now where we have close to that account and will open a new checking account elsewhere. However, because we have a mortgage with this credit Union, we must keep our savings account. I really don't know what to do. That was our savings and our " in case of emergency '' fund. It was being used in case of an emergency, ( my XXXX diagnosis and treatment ). Now, I am fearful that we will face delinquency, possible bankruptcy, foreclosure, you name it. My husband does work full time and I am returning to work full time myself soon, as I need to. I do not have a choice with this happening. It is my worry about what might happen in the interim. it's something gets behind and how we would even going go about figuring out what went wrong? The credit Union doesn't seem to care. Anyhow, I apologize for the long explanation. I locked my account again there is a lender credit check on my account that was done within the last couple months but that should be all. We were looking to refinance for a lower rate. Credit card- I did not apply for. I know better. But, I just don't know what to do in the interim-so wanted to make you aware of this so that you might be able to make the other bureaus aware and point me in the right direction?. If you need to reach me please, definitely do. 
Thank you so much, XXXX XXXX XXXX XXXX XXXX XXXX XXXX