Though you addressed this to the attorney, I’m going to answer also.
You should get a separation agreement drawn up stating what will be her responsibility from the marital debt. There is little that you can do until you do separate to keep her from increasing marital debt.
Once you are separated, all debt incurred by either of you is considered separate and will not be your responsibility. But as far as creditors go, things that have both names on the account means that both of you are equally responsible. After separation or prior, I would suggest closing as many joint accounts as possible.
My question is, IF you are certain that you are going to separate, why allow her to wait until Spring? Especially if you are concerned about her increasing marital debt…Separation can not begin while you are both living in the marital residence and until that time all assets and debts are shared. The separation agreement, regardless of when it is signed will reflect the date that you separate.