Firstly it is not “quick claim deed” it is “Quit Claim Deed”. Getting her to sign a quit claim deed takes her off the title and may terminate her marital interest. To fully terminate her marital interest in the house she needs to sign a separation agreement referencing the quit claim deed. This does not get her off the mortgage. The only way to get her off the mortgage is to refinance in your name. The letter may have weight, but it is not the correct vehicle to do that.
Once you separate any debt you incur after that date is your debt. Debt incurred jointly before them both of you are responsible for. If you can not agree on a way to split up the debt then the court will. That is you have to hire an attorney, file a lawsuit. Maybe you will get out of paying the credit cards, maybe you won’t. A judge would normally split it 50/50, all things being equal. This means you will have to battle it out in court. Divorces are really formalities that say the marriage is over. Separation agreements are where the real work gets done.
The problems with savings is that if you file for bankruptcy that is an asset that must be listed. Bankruptcy is not a get out of jail free card. If you have assets especially cash assets then they have to be used to satisfy some of the debt. Your home cannot be taken to satisfy debt other than the mortgage. If you keep paying the mortgage your home is safe.
Also bankruptcy attorneys usually work on a cash basis.
I don’t know alot about bankruptcy. It is not as easy to do as it use to be. Look here: bankruptcyinformation.com/nc.htm