I have a question for you. BB is going out on a shopping spree and sounds like she may not stop until she maxes out her credit card. It also sounds like she has held herself in check on the buying for a while now. Has this type of shopping orgy occurred before? Is there a pattern of abstinence for a period, then a mad rush to buy all she can?
My impression is that she has been waiting you out, knowing she can outlast you and that it is only a matter of time until she can get you to give in on purchases. Once you concede, she goes full blast, buying as much as she can while the getting’s good. She seems to know exactly what to buy, so I think she has planned this for a while. She was only waiting for the green light from you.
If this is true, she is manipulating you, plain and simple. I know you think everyone should do the right thing, but where do you draw the line on her doing the wrong thing? At this point, the buying is done (or is there more to come?) so your decision over who will pay for it. I’m betting she is thinking you will, since you always have in the past.
I would take hold of the finances. Get off all joint credit cards and checking accounts. If she buy something, let her pay for it. She might become a little more frugal if her credit rating is on the line.
Also, what reason is there not to? In the present situation, you get little to no sex, but she’ll spend you to the poor house. If you cut her off financially, you’ll still get no sex, but at least you’ll have your money.